RESUMEN
The taxonomic position of an actinobacterium, designated CPCC 204279T, which was isolated from a rhizosphere soil sample of the herb Limonium sinense collected from Xinjiang Province, China, was established using a polyphasic approach. Whole-cell hydrolysates of strain CPCC 204279T contained galactose and arabinose as diagnostic sugars and meso-diaminopimelic acid as the diamino acid. The muramic acid residues in the peptidoglycan were N-acetylated. The predominant menaquinone was MK-9(H4). The phospholipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannosides. The major fatty acids were iso-C16 : 0, iso-C16 : 0 2-OH, C16 : 1ω9c, iso-C16 : 1 and C16 : 0. The genomic DNA G+C content was 73.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CPCC 204279T should be placed in the family Pseudonocardiaceae, in which the strain formed a distinct lineage next to the genus Actinophytocola. Signature nucleotides in the 16S rRNA gene sequence showed that the strain contained the Pseudonocardiaceae family-specific 16S rRNA signature nucleotides and a genus-specific diagnostic nucleotide signature pattern. The combination of phylogenetic analysis and phenotypic characteristics supported the conclusion that strain CPCC 204279T represents a novel species of a new genus in the family Pseudonocardiaceae, for which the name Herbihabitans rhizosphaerae gen. nov., sp. nov. is proposed. Strain CPCC 204279T (=NBRC 111774T=DSM 101727T) is the type strain of the type species.
Asunto(s)
Actinomycetales/clasificación , Filogenia , Plumbaginaceae/microbiología , Rizosfera , Microbiología del Suelo , Actinomycetales/genética , Actinomycetales/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Ácidos Murámicos/química , Peptidoglicano/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
An actinobacterium, designated strain CPCC 203993T, was isolated from a rhizosphere soil sample collected from Heilongjiang Province, northeast China, and was characterized using a polyphasic taxonomy approach. Cells of the strain were Gram-stain-positive, non-motile and non-endospore-forming cocci. The 16S rRNA gene sequence comparison of strain CPCC 203993T with members of the genus Microlunatus yielded 93.9 % to 97.8 % similarities. In the phylogenetic tree based on 16S rRNA gene sequences, strain CPCC 203993T was affiliated to the clade of the genus Microlunatus next to Microlunatus parietis DSM 22083T, while the DNA-DNA hybridization value of 31.5 % (±1.8 %) between strain CPCC 203993T and Microlunatus. parietis DSM 22083T was far below 70 %. This result indicated that strain CPCC 203993T represented a different genomic species from M. parietis. Chemotaxonomically, the strain contained ll-2,6-diaminopimelic acid as the diagnostic diamino acid, MK-9(H4) as the only menaquinone, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, three unidentified glycolipids and one unidentified phospholipid in the polar lipids extracts, and anteiso-C15 : 0, iso-C15 : 0 and iso-C16 : 0 as the major cellular fatty acids, without mycolic acids. The genomic DNA G+C content was 64.04 mol%. The above evidence from the polyphasic study merit the recognition of strain CPCC 203993T as a representative of a novel species of the genus Microlunatus, for which Microlunatus nigridraconis sp. nov. is proposed. The type strain is CPCC 203993T (=DSM 29529T=NBRC 110715T=KCTC 29689T).
Asunto(s)
Filogenia , Propionibacteriaceae/clasificación , Rizosfera , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Fosfolípidos/química , Propionibacteriaceae/genética , Propionibacteriaceae/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
A microcystin-degrading strain, designated CPCC 100154(T), was isolated from a forest soil sample collected from Hainan Island, South China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CPCC 100154(T) is affiliated to the family Sinobacteraceae in Gammaproteobacteria, with high 16S rRNA gene sequence similarities of 98.1, 96.6 and 96.6 % to Steroidobacter agariperforans JCM 18477(T), S. denitrificansis DSM 18526(T), and Povalibacter uvarum JCM 18749(T), respectively. In the phylogenetic tree based on 16S rRNA gene sequences, strain CPCC 100154(T) formed a stable phylogenetic subclade with S. agariperforans JCM 18477(T), which indicated that strain CPCC 100154(T) should be identified as a member of the genus Steroidobacter. The phylogenetic analysis based on partial gyrB gene sequences confirmed the affiliation of strain CPCC 100154(T) to the genus Steroidobacter. While the DNA-DNA hybridization value (47.0 ± 1.7 %) between the new isolate and its near phylogenetic neighbor S. agariperforans JCM 18477(T) was far below 70 %, which demonstrated that strain CPCC 100154(T) represents a different genomic species from S. agariperforans. The strain CPCC 100154(T) was found to be a Gram-stain negative, rod-shaped, motile with a polar flagellum, non-endospore-forming bacterium. Good growth was observed at 28-32 °C and pH 7.0-7.5. Polar lipids were identified to be diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, a unidentified phospholipid, an aminophospholipid and an unidentified aminolipid. The polyamine pattern was determined to contain spermidine as the predominant polyamine, moderate amounts of putrescine as well as traces of sym-homospermidine and spermine. The respiratory quinone was identified as ubiquinone-8. The major cellular fatty acids were found to include summed feature 3 (C16: 1 ω7C/C16: 1 ω6C) (46.1 %) and C16: 0 (29.6 %). The genomic DNA G+C content was determined to be 64.4 mol%. On the basis of the above polyphasic taxonomy evidence, a novel species, Steroidobacter flavus sp. nov. is proposed. The type strain is CPCC 100154(T) (=DSM 23339(T) =CGMCC 1.10759(T)).
Asunto(s)
Gammaproteobacteria/aislamiento & purificación , Gammaproteobacteria/metabolismo , Microcistinas/metabolismo , Secuencia de Bases , China , Ácidos Grasos/metabolismo , Bosques , Gammaproteobacteria/genética , Lípidos/análisis , Hibridación de Ácido Nucleico , Fosfolípidos/metabolismo , Quinonas/metabolismo , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Suelo , Microbiología del Suelo , Ubiquinona/metabolismoRESUMEN
OBJECTIVE: To investigate the resistant effect of houttuyfonate sodium (SH) combined with imipenem (IMP) against Pseudomonas aeruginosa (Pa) biofilms. METHOD: The two-fold dilution method was used to examine the minimum inhibitory concentration (MIC) of the tested drug. The crystal violet staining was applied to detect the effect of the combination of 1/2MIC, 1MIC, 2MIC of SH, single IMP, 1/2MIC of SH and IMP of various concentrations on the clearance rate of adherent bacteria, growth of biofilms and alginate production. Fluorescein diacetate (FDA)-propidium iodide (PI) doubling staining assay was employed to observe the bacterial viability and morphological changes after membrane dispersion of each drug group. RESULT: Sodium houttuyfonate could enhance the effect of IMP against pseudomonas aeruginosa biofilms. Particularly, the combination group with the concentration of 2MIC showed the highest effect, with P < 0.001 compared with the negative control group. The above results were proved by the bacterial viability and biofilm morphology under fluorescence microscope. CONCLUSION: After being combined with imipenem, sodium houttuyfonate shows a higher effect against biofilms. It is expected that the combination of the two drugs could improve the clinical efficacy of associated infections.