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1.
Front Microbiol ; 15: 1432475, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39282555

RESUMEN

A considerable number of antibacterial agents are derived from bacterial metabolites. Similarly, numerous known compounds that impede bacterial virulence stem from bacterial metabolites. Enteropathogenic Escherichia coli (EPEC) is a notable human pathogen causing intestinal infections, particularly affecting infant mortality in developing regions. These infections are characterized by microvilli effacement and intestinal epithelial lesions linked with aberrant actin polymerization. This study aimed to identify potential antivirulence compounds for EPEC infections among bacterial metabolites harvested from marine actinobacteria (Kocuria sp. and Rhodococcus spp.) from the Arctic Sea by the application of virulence-based screening assays. Moreover, we demonstrate the suitability of these antivirulence assays to screen actinobacteria extract fractions for the bioassay-guided identification of metabolites. We discovered a compound in the fifth fraction of a Kocuria strain that interferes with EPEC-induced actin polymerization without affecting growth. Furthermore, a growth-inhibiting compound was identified in the fifth fraction of a Rhodococcus strain. Our findings include the bioassay-guided identification, HPLC-MS-based dereplication, and isolation of a large phospholipid and a likely antimicrobial peptide, demonstrating the usefulness of this approach in screening for compounds capable of inhibiting EPEC virulence.

2.
Chemosphere ; 364: 143085, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39146985

RESUMEN

Airborne Organic Pollutants (AOPs) reach remote oceanic regions after long range atmospheric transport and deposition, incorporating into natural microbial communities. This study investigated the effects of AOPs on natural microbial communities of the Mediterranean Sea, the Atlantic Ocean and the Bellingshausen Sea, by assessing the impact of both non-polar and polar AOPs on cell abundances, chlorophyll a concentrations and cell viabilities of different microbial groups. Our results indicate that almost all groups, except flagellates in the Bellingshausen Sea, were significantly affected by AOPs. While no significant differences in chlorophyll a concentrations were observed between non-polar and polar AOPs, significant variations in cell abundances were noted. Cell death occurred at AOP concentrations as low as five times the oceanic field levels, likely due to their high chemical activity. Cyanobacteria in temperate waters exhibited the highest sensitivity to AOPs, whereas medium and larger diatoms in the Bellingshausen Sea were more affected than smaller diatoms or flagellates, contrary to the expected size-related sensitivity trend. Additionally, microorganisms in temperate waters were more sensitive to the polar fraction of AOPs compared to the non-polar fraction, which showed an inverse sensitivity pattern. This differential sensitivity is attributed to variations in the ratio of polar to non-polar AOPs in the respective environments. Our findings underscore the varying impacts of AOPs on marine microbial communities across different oceanic regions.

3.
Mar Environ Res ; 199: 106624, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38943698

RESUMEN

Marine bacteria influence Earth's environmental dynamics in fundamental ways by controlling the biogeochemistry and productivity of the oceans. However, little is known about the survival strategies of their abundant and rare taxa, especially in polar marine environments. Here, bacterial environmental adaptation, community assembly processes, and co-occurrence patterns between abundant and rare taxa were compared in the Arctic Ocean sediments. Results indicated that the diversity of rare taxa is significantly higher than that of abundant taxa, whereas the distance-decay rate of rare taxa community similarity is over 1.5 times higher than that of abundant taxa. Furthermore, abundant taxa exhibited broader environmental breadth and stronger phylogenetic signals compared to rare taxa. Additionally, the community assembly processes of the abundant taxa were predominantly governed by 81% dispersal limitation, while rare taxa were primarily influenced by 48% heterogeneous selection. The co-occurrence network further revealed the abundant taxa formed a more complex network to enhance their environmental adaptability. This study revealed the differences in environmental responses and community assembly processes between bacterial abundant and rare taxa in polar ocean sediments, providing some valuable insights for understanding their environmental adaptation strategies in marine ecosystems.


Asunto(s)
Bacterias , Sedimentos Geológicos , Océanos y Mares , Regiones Árticas , Sedimentos Geológicos/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Biodiversidad , Filogenia , Ecosistema , Adaptación Fisiológica , Agua de Mar/microbiología
4.
PeerJ ; 12: e17165, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38590706

RESUMEN

Background: Plastic waste is a global environmental issue that impacts the well-being of humans, animals, plants, and microorganisms. Microplastic contamination has been previously reported at Kung Wiman Beach, located in Chanthaburi province along with the Eastern Gulf of Thailand. Our research aimed to study the microbial population of the sand and plastisphere and isolate microorganisms with potential plastic degradation activity. Methods: Plastic and sand samples were collected from Kung Wiman Beach for microbial isolation on agar plates. The plastic samples were identified by Fourier-transform infrared spectroscopy. Plastic degradation properties were evaluated by observing the halo zone on mineral salts medium (MSM) supplemented with emulsified plastics, including polystyrene (PS), polylactic acid (PLA), polyvinyl chloride (PVC), and bis (2-hydroxyethyl) terephthalate (BHET). Bacteria and fungi were identified by analyzing nucleotide sequence analysis of the 16S rRNA and internal transcribed spacer (ITS) regions, respectively. 16S and ITS microbiomes analysis was conducted on the total DNA extracted from each sample to assess the microbial communities. Results: Of 16 plastic samples, five were identified as polypropylene (PP), four as polystyrene (PS), four as polyethylene terephthalate (PET), two as high-density polyethylene (HDPE), and one sample remained unidentified. Only 27 bacterial and 38 fungal isolates were found to have the ability to degrade PLA or BHET on MSM agar. However, none showed degradation capabilities for PS or PVC on MSM agar. Notably, Planococcus sp. PP5 showed the highest hydrolysis capacity of 1.64 ± 0.12. The 16S rRNA analysis revealed 13 bacterial genera, with seven showing plastic degradation abilities: Salipiger, Planococcus, Psychrobacter, Shewanella, Jonesia, Bacillus, and Kocuria. This study reports, for the first time of the BHET-degrading properties of the genera Planococcus and Jonesia. Additionally, The ITS analysis identified nine fungal genera, five of which demonstrated plastic degradation abilities: Aspergillus, Penicillium, Peacilomyces, Absidia, and Cochliobolus. Microbial community composition analysis and linear discriminant analysis effect size revealed certain dominant microbial groups in the plastic and sand samples that were absent under culture-dependent conditions. Furthermore, 16S and ITS amplicon microbiome analysis revealed microbial groups were significantly different in the plastic and sand samples collected. Conclusions: We reported on the microbial communities found on the plastisphere at Kung Wiman Beach and isolated and identified microbes with the capacity to degrade PLA and BHET.


Asunto(s)
Actinomycetales , Microbiota , Actinomycetales/genética , Agar/metabolismo , Bacterias/genética , Microbiota/genética , Plásticos/metabolismo , Poliésteres/metabolismo , Poliestirenos/metabolismo , ARN Ribosómico 16S/genética , Arena
5.
Arch Microbiol ; 206(3): 103, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38358529

RESUMEN

Heavy metals (HMs) like Zn, Cu, Pb, Ni, Cd, and Hg, among others, play a role in several environmental problems. The marine environment is polluted by several contaminants, such as HMs. A variety of physico-chemical methods usually available for sanitation HMs remediation suffer from either limitation. Bioremediation is a promising way of dealing with HMs pollution. Microbes have the ability with various potencies to resist HMs tension. The current review discusses the main sources and influences of HMs, the role of marine microorganisms in HMs bioremediation, as well as the microbial mechanisms for HMs detoxification and transformation. This review paper aims to provide an overview of the bioremediation technologies that are currently available for the removal of HMs ions from industrial and urban effluent by aquatic organisms such as bacteria, fungi, and microalgae, particularly those that are isolated from marine areas. The primary goals are to outline various studies and offer helpful information about the most important aspects of the bioelimination techniques. The biotreatment practices have been primarily divided into three techniques based on this topic. They are biosorption, bioaccumulation, bioleaching, and biotransformation. This article gives the brief view on the research studies about bioremediation of HMs using marine microorganisms. The current review also deals with the critical issues and recent studies based on the HMs biodetoxification using aquatic microorganisms.


Asunto(s)
Metales Pesados , Microalgas , Biodegradación Ambiental , Industrias
6.
Bioelectrochemistry ; 157: 108659, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38330530

RESUMEN

The issue of material failure attributed to microbiologically influenced corrosion (MIC) is escalating in seriousness. Microorganisms not only facilitate corrosion but certain beneficial microorganisms also impede its occurrence. This study explored the impact of marine B. velezensis on the corrosion behavior of X65 steel in simulated offshore oilfield produced water. B. velezensis exhibited rapid growth in the initial stages, and the organic acid metabolites were found to promote corrosion. Subsequently, there was an increase in cross-linked "networked" biofilms products, a significant rise in the prismatic shape of corrosion products, and a tendency for continuous development in the middle and late stages. The organic/inorganic mineralized film layer formed on the surface remained consistently complete. Metabolic products of amino acid corrosion inhibitors were also observed to be adsorbed into the film. B. velezensis altered the kinetics of the X65 steel cathodic reaction, resulting in a deceleration of the electrochemical reaction rate. The mineralization induced by B. velezensis effectively slowed down the corrosion rate of X65 steel.


Asunto(s)
Bacillus , Acero , Acero/química , Agua , Corrosión , Biomineralización , Yacimiento de Petróleo y Gas , Biopelículas
7.
Microorganisms ; 12(1)2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38257972

RESUMEN

Lignocellulosic materials are composed of cellulose, hemicellulose and lignin and are one of the most abundant biopolymers in marine environments. The extent of the involvement of marine microorganisms in lignin degradation and their contribution to the oceanic carbon cycle remains elusive. In this study, a novel lignin-degrading bacterial strain, LCG003, was isolated from intertidal seawater in Lu Chao Harbor, East China Sea. Phylogenetically, strain LCG003 was affiliated with the genus Aliiglaciecola within the family Alteromonadaceae. Metabolically, strain LCG003 contains various extracellular (signal-fused) glycoside hydrolase genes and carbohydrate transporter genes and can grow with various carbohydrates as the sole carbon source, including glucose, fructose, sucrose, rhamnose, maltose, stachyose and cellulose. Moreover, strain LCG003 contains many genes of amino acid and oligopeptide transporters and extracellular peptidases and can grow with peptone as the sole carbon and nitrogen source, indicating a proteolytic lifestyle. Notably, strain LCG003 contains a gene of dyp-type peroxidase and strain-specific genes involved in the degradation of 4-hydroxy-benzoate and vanillate. We further confirmed that it can decolorize aniline blue and grow with lignin as the sole carbon source. Our results indicate that the Aliiglaciecola species can depolymerize and mineralize lignocellulosic materials and potentially play an important role in the marine carbon cycle.

8.
Artículo en Inglés | MEDLINE | ID: mdl-37889453

RESUMEN

Antimicrobial resistance is an important health concern globally, and probiotics are considered an alternative to minimize it. The present study examined the in vitro probiotic characteristics and in vivo immunomodulatory potential of Bacillus sp. 62A - an extremophile bacterium. Bacillus sp. 62A was evaluated in vitro for its cytotoxicity, hemolytic activity, antibiotic susceptibility, and resistance to gastrointestinal conditions (bile salts, low pH, and intestinal adherence). Additionally, the immunomodulatory effect of Bacillus sp. 62A was studied in mice. The animals were supplemented daily with phosphate-buffered saline (control) and Bacillus sp. 62A at 1 × 108 colony forming units (CFU). Samples were taken on days 5 and 10. Isolated splenocytes were challenged with Escherichia coli for immunological analyses and immune-related gene expression. Serum and feces were collected for IgA and IgG determination. Bacillus sp. 62A did not show cytotoxicity, hemolytic activity, or resistance to antibiotics. Furthermore, the bacterium has autoaggregation and intestinal adhesion capacities and grows in the presence of bile salts and low pH. Bacillus supplementation in mice improved respiratory burst activity, nitric oxide production, and IL-1ß and IL-6 gene expressions, mainly at 10 days. After E. coli challenge, Bacillus supplementation in mice induced an anti-inflammatory response through a decrease in immunological parameters and an increase in IL-10 gene expression. Moreover, serum IgA and IgG and fecal IgG augmented in supplemented mice. In conclusion, Bacillus sp. 62A has biosafe and immunomodulatory probiotic potential.

9.
BMC Genomics ; 24(1): 550, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37723472

RESUMEN

BACKGROUND: Phosphorus is one of the essential nutrients for plant growth. Phosphate-solubilizing microorganisms (PSMs) can alleviate available P deficiency and enhance plant growth in an eco-friendly way. Although ammonium toxicity is widespread, there is little understanding about the effect of ammonium stress on phosphorus solubilization (PS) of PSMs. RESULTS: In this study, seven PSMs were isolated from mangrove sediments. The soluble phosphate concentration in culture supernatant of Bacillus aryabhattai NM1-A2 reached a maximum of 196.96 mg/L at 250 mM (NH4)2SO4. Whole-genome analysis showed that B. aryabhattai NM1-A2 contained various genes related to ammonium transporter (amt), ammonium assimilation (i.e., gdhA, gltB, and gltD), organic acid synthesis (i.e., ackA, fdhD, and idh), and phosphate transport (i.e., pstB and pstS). Transcriptome data showed that the expression levels of amt, gltB, gltD, ackA and idh were downregulated, while gdhA and fdhD were upregulated. The inhibition of ammonium transporter and glutamine synthetase/glutamate synthase (GS/GOGAT) pathway contributed to reducing energy loss. For ammonium assimilation under ammonium stress, accompanied by protons efflux, the glutamate dehydrogenase pathway was the main approach. More 2-oxoglutarate (2-OG) was induced to provide abundant carbon skeletons. The downregulation of formate dehydrogenase and high glycolytic rate resulted in the accumulation of formic acid and acetic acid, which played key roles in PS under ammonium stress. CONCLUSIONS: The accumulation of 2-OG and the inhibition of GS/GOGAT pathway played a key role in ammonium detoxification. The secretion of protons, formic acid and acetic acid was related to PS. Our work provides new insights into the PS mechanism, which will provide theoretical guidance for the application of PSMs.


Asunto(s)
Fósforo , Protones , Fosfatos , Ácido Acético
10.
J Appl Microbiol ; 134(7)2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37365690

RESUMEN

Aquaculture, a noteworthy food production sector, is confronted with disease occurrences. Treatment of aquaculture pathogens with antibiotics is often rendered ineffective due to biofilm formation and the development of resistant strains. Marine ecosystems encompass unusual microorganisms that produce novel bioactive compounds, including agents that could be used as alternatives to antibiotics. Moreover, biomass and/or biomolecules associated with these microorganisms could act as feed supplements to enhance the overall health of aquaculture species' and improve water quality parameters. The present review summarizes the contents of studies on such marine microorganisms with the potential to be developed as agents for tackling bacterial diseases in the aquaculture segment. Bioactive compounds produced by marine bacteria are known to inhibit biofilm-associated infections mediated by their bactericidal properties (produced by Bacillus, Vibrio, Photobacterium, and Pseudoalteromonas species), surfactant activity (obtained from different species of Bacillus and Staphylococcus lentus), anti-adhesive activity (derived from Bacillus sp. and Brevibacterium sp.), and quorum sensing inhibition. Several marine fungal isolates capable of producing antibacterial agents have also been effective in inhibiting aquaculture-associated pathogens. Another strategy followed by investigators to reduce the severity of infections is the use of bacterial, yeast, and microalgae biomass as feed supplements, probiotics, and immunostimulants. In some cases, marine microalgae have been employed as sustainable alternatives to fish oil and fish meal without compromising on nutritional quality. Their inclusion in aquaculture feed has enhanced growth, favored better survival of cultured species, and improved water quality parameters. Marine microorganisms (by providing effective bioactive compounds and being used as feed supplements) could enable aquaculture practices to be more sustainable in the future.


Asunto(s)
Antiinfecciosos , Bacillus , Vibrio , Ecosistema , Acuicultura , Antiinfecciosos/farmacología , Antibacterianos/farmacología
11.
Animals (Basel) ; 13(7)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37048497

RESUMEN

Although several studies have described the bacterial community composition associated with marine fish, there is limited information related to seahorses. Moreover, previous studies have demonstrated that the skin microbiota is useful for determining health status and common disorders in the host. This study, therefore, aimed to explore the skin bacterial community composition in Barbour's seahorse (Hippocampus barbouri) using high-throughput sequencing of 16S ribosomal RNA genes. Water and sediment samples from the surrounding environment were also analyzed for comparative purposes. The results revealed that sequences affiliated with the Shewanellaceae family were dominant in the skin of female Barbour's seahorses and sediment samples, whereas sequences affiliated with the Bacillaceae family were dominant in the skin of male Barbour's seahorses. Interestingly, sequences affiliated with the Aeromonas genus were found in the skin of Barbour's seahorses, whose abundance was slightly similar between the female and male specimens. Further comparative analysis showed that the presence of Aeromonas species in the skin of Barbour's seahorses was strongly influenced by the surrounding sediment. Given that some Aeromonas species are known to be important pathogens in humans and fish, these results may be used for further research on the dependency of the skin microbial composition on the environment as well as determine whether the presence of Aeromonas and other detected species has implications on seahorse health.

12.
Eur J Med Chem ; 252: 115330, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37011553

RESUMEN

The emergence of drug-resistant Vibrio poses a serious threat to aquaculture and human health, thus there is an urgent need for the discovery of new related antibiotics. Given that marine microorganisms (MMs) are evidenced as important sources of antibacterial natural products (NPs), great attention has been gained to the exploration of potential anti-Vibrio agents from MMs. This review summarizes the occurrence, structural diversity, and biological activities of 214 anti-Vibrio NPs isolated from MMs (from 1999 to July 2022), including 108 new compounds. They were predominantly originated from marine fungi (63%) and bacteria (30%) with great structural diversity, including polyketides, nitrogenous compounds, terpenoids, and steroids, among which polyketides account for nearly half (51%) of them. This review will shed light on the development of MMs derived NPs as potential anti-Vibrio lead compounds with promising applications in agriculture and human health.


Asunto(s)
Productos Biológicos , Policétidos , Humanos , Productos Biológicos/farmacología , Productos Biológicos/química , Hongos/química , Antibacterianos/farmacología , Antibacterianos/química , Bacterias/química , Organismos Acuáticos/química
13.
Front Microbiol ; 14: 1127308, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36876073

RESUMEN

Marine microplastic pollution is a growing problem for ecotoxicology that needs to be resolved. In particular, microplastics may be carriers of "dangerous hitchhikers," pathogenic microorganisms, i.e., Vibrio. Microplastics are colonized by bacteria, fungi, viruses, archaea, algae and protozoans, resulting in the biofilm referred to as the "plastisphere." The microbial community composition of the plastisphere differs significantly from those of surrounding environments. Early dominant pioneer communities of the plastisphere belong to primary producers, including diatoms, cyanobacteria, green algae and bacterial members of the Gammaproteobacteria and Alphaproteobacteria. With time, the plastisphere mature, and the diversity of microbial communities increases quickly to include more abundant Bacteroidetes and Alphaproteobacteria than natural biofilms. Factors driving the plastisphere composition include environmental conditions and polymers, with the former having a much larger influence on the microbial community composition than polymers. Microorganisms of the plastisphere may play key roles in degradation of plastic in the oceans. Up to now, many bacterial species, especially Bacillus and Pseudomonas as well as some polyethylene degrading biocatalysts, have been shown to be capable of degrading microplastics. However, more relevant enzymes and metabolisms need to be identified. Here, we elucidate the potential roles of quorum sensing on the plastic research for the first time. Quorum sensing may well become a new research area to understand the plastisphere and promote microplastics degradation in the ocean.

14.
Microorganisms ; 11(3)2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36985270

RESUMEN

Despite considerable advances in medicine and technology, humanity still faces many deadly diseases such as cancer and malaria. In order to find appropriate treatments, the discovery of new bioactive substances is essential. Therefore, research is now turning to less frequently explored habitats with exceptional biodiversity such as the marine environment. Many studies have demonstrated the therapeutic potential of bioactive compounds from marine macro- and microorganisms. In this study, nine microbial strains isolated from an Indian Ocean sponge, Scopalina hapalia, were screened for their chemical potential. The isolates belong to different phyla, some of which are already known for their production of secondary metabolites, such as the actinobacteria. This article aims at describing the selection method used to identify the most promising microorganisms in the field of active metabolites production. The method is based on the combination of their biological and chemical screening, coupled with the use of bioinformatic tools. The dereplication of microbial extracts and the creation of a molecular network revealed the presence of known bioactive molecules such as staurosporin, erythromycin and chaetoglobosins. Molecular network exploration indicated the possible presence of novel compounds in clusters of interest. The biological activities targeted in the study were cytotoxicity against the HCT-116 and MDA-MB-231 cell lines and antiplasmodial activity against Plasmodium falciparum 3D7. Chaetomium globosum SH-123 and Salinispora arenicola SH-78 strains actually showed remarkable cytotoxic and antiplasmodial activities, while Micromonospora fluostatini SH-82 demonstrated promising antiplasmodial effects. The ranking of the microorganisms as a result of the different screening steps allowed the selection of a promising strain, Micromonospora fluostatini SH-82, as a premium candidate for the discovery of new drugs.

15.
Mar Drugs ; 20(10)2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36286449

RESUMEN

The marine environment is important yet generally underexplored. It contains new sources of functional constituents that can affect various pathways in food processing, storage, and fortification. Bioactive secondary metabolites produced by marine microorganisms may have significant potential applications for humans. Various components isolated from disparate marine microorganisms, including fungi, microalgae, bacteria, and myxomycetes, showed considerable biological effects, such as anticancer, antioxidant, antiviral, antibacterial, and neuroprotective activities. Growing studies are revealing that potential anticancer effects of marine agents could be achieved through the modulation of several organelles. Mitochondria are known organelles that influence growth, differentiation, and death of cells via influencing the biosynthetic, bioenergetic, and various signaling pathways related to oxidative stress and cellular metabolism. Consequently, mitochondria play an essential role in tumorigenesis and cancer treatments by adapting to alterations in environmental and cellular conditions. The growing interest in marine-derived anticancer agents, combined with the development and progression of novel technology in the extraction and cultures of marine life, led to revelations of new compounds with meaningful pharmacological applications. This is the first critical review on marine-derived anticancer agents that have the potential for targeting mitochondrial function during tumorigenesis. This study aims to provide promising strategies in cancer prevention and treatment.


Asunto(s)
Antineoplásicos , Productos Biológicos , Neoplasias , Humanos , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Mitocondrias , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antibacterianos , Antivirales/farmacología , Neoplasias/tratamiento farmacológico , Carcinogénesis , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Organismos Acuáticos
16.
Mar Drugs ; 20(8)2022 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-36005515

RESUMEN

The unique living environment of marine microorganisms endows them with the potential to produce novel chemical compounds with various biological activities. Among them, the exopolysaccharides produced by marine microbes are an important factor for them to survive in these extreme environments. Up to now, exopolysaccharides from marine microbes, especially from extremophiles, have attracted more and more attention due to their structural complexity, biodegradability, biological activities, and biocompatibility. With the development of culture and separation methods, an increasing number of novel exopolysaccharides are being found and investigated. Here, the source, structure and biological activities of exopolysaccharides, as well as their potential applications in environmental restoration fields of the last decade are summarized, indicating the commercial potential of these versatile EPS in different areas, such as food, cosmetic, and biomedical industries, and also in environmental remediation.


Asunto(s)
Polisacáridos Bacterianos , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/farmacología
17.
J Appl Microbiol ; 133(5): 2779-2789, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35870151

RESUMEN

AIM: Since the hot water of Genow, a village in Isin rural district in the central district of Bandar Abbas, Hormozgan Province, Iran, has a rich source of thermophilic bacteria, the current study aimed to find a new thermophilic protease enzyme with suitable properties to be used in different industries. METHODS AND RESULTS: Water and sediment samples were collected from the hot water of Genow, and finally, 20 colonies were isolated. Among these isolated colonies, two bacterial strains grew on the skim milk agar medium, and a clear halo was formed around the colony, which was accurately identified by 16S rRNA gene sequence analysis. The comparison of 16S rRNA gene sequence analyses of isolated strains HR01 and HR02 with registered sequences of 16S rRNA genes in NCBI showed that the two isolates had the most similarity to Bacillus sonorensis and Bacillus subtilis, respectively. Among the two bacterial strains, the highest enzymatic activity was observed in B. subtilis strain HR02, from which the protease purification process was performed. A putative native B. subtilis strain HR02 protease (BSHR02PR) was purified by the UNO Q-6 ionic exchange chromatography method. Biochemical analyses revealed a monomeric enzyme, BsHR02Pro, with a molecular weight of 25 kDa, showing the maximum activity at 70°C and pH 8.0. Moreover, the purified enzyme was stable up to 80 °C and in a pH range of 6.0-12.0. The steady-state kinetic analysis for colloidal casein showed that the Km , Vmax and kcat values of the purified enzyme were 25.7 µM, 93.2 µM min-1 and 2.18 s-1 , respectively. CONCLUSION: The hot water of Genow is a rich source of protease-producing bacteria. Sediments are a better source for the isolation of these types of bacteria than spring water. Overall, our results demonstrated a potential bacterial enzyme BsHR02Pro as a suitable catalyst to be used in the various industries.


Asunto(s)
Bacillus subtilis , Péptido Hidrolasas , Péptido Hidrolasas/genética , Péptido Hidrolasas/metabolismo , ARN Ribosómico 16S/genética , Cinética , Caseínas , Agar , Proteínas Bacterianas/química , Endopeptidasas , Agua , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Temperatura
18.
Can J Microbiol ; 68(9): 576-582, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35759795

RESUMEN

Thirteen aerobic, halotolerant marine bacterial strains were isolated from the mantle fluids and associated mucus of the eastern oyster Crassostrea virginica harvested from the highly impacted Black Rock Harbor in western Long Island Sound. All isolated strains were Gram negative and had previously been identified using 16S RNA gene sequence analysis. These 13 strains were examined for their ability to inhibit the growth of each other employing a diffusion agar method used by antibiotic assays. All challenger strains were able to inhibit at least one of the indicator isolates. Enhanced antimicrobial activity was observed from cultures of Pseudoalteromonas sp. (L), Shewanella sp. (H), Thalassospira sp. (JA), and Alteromonas sp. (JB) when used to challenge the indicator isolates. The indicator isolate most sensitive to antimicrobial activity was another Pseudoalteromonas species (KC) whose growth was inhibited by 10 of the challenger strains, whereas Pseudoalteromonas (L) was resistant to all growth challenges. Growth autoinhibition was observed with isolates Tenacibaculum ascidiaceicola (KC), Vibrio (B), and Shewanella (H) during a 24 h incubation. No antimicrobial growth inhibition was detected when 24 and 48 h cell-free extracts of these isolates were used to challenge indicator isolate growth.


Asunto(s)
Crassostrea , Vibrio , Agar , Animales , Antibacterianos , Crassostrea/genética , Crassostrea/microbiología , Filogenia , ARN , ARN Ribosómico 16S/genética , Vibrio/genética
19.
Sci Total Environ ; 836: 155445, 2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-35490806

RESUMEN

Cancer is one of the most deadly diseases on the planet. Over the past decades, numerous antineoplastic compounds have been discovered from natural resources such as medicinal plants and marine species as part of multiple drug discovery initiatives. Notably, several marine flora (e.g. Ascophyllum nodosum, Sargassum thunbergii) have been identified as a rich source for novel cytotoxic compounds of different chemical forms. Despite the availability of enormous chemically enhanced new resources, the anticancer potential of marine flora and fauna has received little attention. Interestingly, numerous marine-derived secondary metabolites (e.g., Cytarabine, Trabectedin) have exhibited anticancer effects in preclinical cancer models. Most of the anticancer drugs obtained from marine sources stimulated apoptotic signal transduction pathways in cancer cells, such as the intrinsic and extrinsic pathways. This review highlights the sources of different cytotoxic secondary metabolites obtained from marine bacteria, algae, fungi, invertebrates, and vertebrates. Furthermore, this review provides a comprehensive overview of the utilisation of numerous marine-derived cytotoxic compounds as anticancer drugs, as well as their modes of action (e.g., molecular target). Finally, it also discusses the future prospects of marine-derived drug developments and their constraints.


Asunto(s)
Antineoplásicos , Productos Biológicos , Neoplasias , Animales , Antineoplásicos/química , Organismos Acuáticos/metabolismo , Productos Biológicos/química , Descubrimiento de Drogas , Ecosistema
20.
Lett Appl Microbiol ; 75(3): 511-525, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35485872

RESUMEN

Marine micro-organisms are a promising source for novel natural compounds with many medical and biotechnological applications. Here, we demonstrate limitations and recent strategies for investigating the marine microbial community for novel bioactive metabolites, specifically those of antimicrobial potential. These strategies include culture-dependent methods such as modifying the standard culture media, including changing the gelling agent, dissolving vehicle, media supplementation and preparation to access a broader range of bacterial diversity from marine samples. Furthermore, we discuss strategies such as in situ cultivation, dilution-to-extinction cultivation and long-term incubation. We are presenting recent applications of culture-independent methods such as genome mining, proteomics profiling and the application of metagenomics as a novel strategy for structure confirmation in the discovery of the marine micro-organism for novel antimicrobial metabolites. We present this review as a simple guide and a helpful resource for those who seek to enter the challenging field of applied marine microbiology.


Asunto(s)
Antiinfecciosos , Productos Biológicos , Antibacterianos/metabolismo , Antibacterianos/farmacología , Antiinfecciosos/química , Organismos Acuáticos , Bacterias/metabolismo , Productos Biológicos/farmacología , Medios de Cultivo/metabolismo , Metagenómica
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