RESUMO

Marine macroalgae are emerging as an untapped source of novel microbial diversity and, therefore, of new bioactive secondary metabolites. This study was aimed at assessing the diversity and antimicrobial activity of the culturable Gram-positive bacteria associated with the surface of three co-occurring Antarctic macroalgae. Specimens of Adenocystis utricularis (brown alga), Iridaea cordata (red alga) and Monostroma hariotii (green alga) were collected from the intertidal zone of King George Island, Antarctica. Gram-positive bacteria were investigated by cultivation-based methods and 16S rRNA gene sequencing, and screened for antimicrobial activity against a panel of pathogenic microorganisms. Isolates were found to belong to 12 families, with a dominance of Microbacteriaceae and Micrococcaceae. Seventeen genera of Actinobacteria and 2 of Firmicutes were cultured from the three macroalgae, containing 29 phylotypes. Three phylotypes within Actinobacteria were regarded as potentially novel species. Sixteen isolates belonging to the genera Agrococcus, Arthrobacter, Micrococcus, Pseudarthrobacter, Pseudonocardia, Sanguibacter, Staphylococcus, Streptomyces and Tessaracoccus exhibited antibiotic activity against at least one of the indicator strains. The bacterial phylotype composition was distinct among the three macroalgae species, suggesting that these macroalgae host species-specific Gram-positive associates. The results highlight the importance of Antarctic macroalgae as a rich source of Gram-positive bacterial diversity and potentially novel species, and a reservoir of bacteria producing biologically active compounds with pharmacological potential.

Assuntos

RESUMO

Little is known about the diversity and roles of Gram-positive and pigmented bacteria in Antarctic environments, especially those associated with marine macroorganisms. This work is the first study about the diversity and antimicrobial activity of culturable pigmented Gram-positive bacteria associated with marine Antarctic macroalgae. A total of 31 pigmented Gram-positive strains were isolated from the surface of six species of macroalgae collected in the King George Island, South Shetland Islands. On the basis of 16S rRNA gene sequence similarities ≥99%, 18 phylotypes were defined, which were clustered into 11 genera of Actinobacteria (Agrococcus, Arthrobacter, Brachybacterium, Citricoccus, Kocuria, Labedella, Microbacterium, Micrococcus, Rhodococcus, Salinibacterium and Sanguibacter) and one genus of the Firmicutes (Staphylococcus). It was found that five isolates displayed antimicrobial activity against a set of macroalgae-associated bacteria. The active isolates were phylogenetically related to Agrococcus baldri, Brachybacterium rhamnosum, Citricoccus zhacaiensis and Kocuria palustris. The results indicate that a diverse community of pigmented Gram-positive bacteria is associated with Antartic macroalgae and suggest its potential as a promising source of antimicrobial and pigmented natural compounds.

Assuntos

RESUMO

La cirugía ambulatoria cubre un amplio espectro de procedimientos quirúrgicos mayores. La colecistectomía laparoscópica fue reportada por primera vez por Mouret en Francia en 1987, y es ahora considerada el abordaje "gold standard". En 1996 se implementó como un procedimiento quirúrgico de día. Para la realización de cirugías ambulatorias es necesaria una Unidad con infraestructura destinada para tal fin. En el Hospital Nacional Rosales, a principios de año 2013, la Cirugía Mayor Ambulatoria se presentó como un proyecto de programa organizado y delimitado. Se realizó un estudio observacional descriptivo, longitudinal, de tipo prospectivo de seguimiento de la cohorte de pacientes programados para colecistectomía laparoscópica ambulatoria en Hospital Nacional Rosales en el periodo del 1ero de mayo 2014 al 30 de mayo del 2015. Se encontró un total de 205 colecistectomías laparoscópicas: 182 mujeres y 33 hombres. La mediana de edad en la población fue de 41 años. 73.02% residían en San Salvador. El 92% de los pacientes eran ASA I y II. El 100% tenían criterios para colecistectomía laparoscópica. El 94.4% tenían criterios sociales para cirugía ambulatoria. La tasa de suspensión de cirugía fue de 10.48%. De las cirugías realizadas: la tasa de conversión fue de 1.95%, por adherencia (3) y Síndrome de Mirizzi (1). La tasa de ingreso hospitalario fue de 15.12%, la causa más frecuente fueron las complicaciones transoperatorias. No hubo reingresos ni mortalidad. En conclusión el programa de colecistectomía laparoscópica ambulatoria en el HNR es un procedimiento seguro

Outpatient surgery covers a wide spectrum of major surgical procedures. Laparoscopic cholecystectomy was first reported by Mouret in France in 1987, and is now considered the "gold standard" approach. In 1996 it was implemented as a day surgical procedure. To perform outpatient surgeries, a Unit with an infrastructure designed for this purpose is necessary. At the Hospital Nacional Rosales, at the beginning of 2013, the Major Ambulatory Surgery was presented as an organized and delimited program project. An observational, descriptive, longitudinal, prospective follow-up study was carried out on the cohort of patients scheduled for outpatient laparoscopic cholecystectomy at Hospital Nacional Rosales in the period from May 1, 2014 to May 30, 2015. A total of 205 laparoscopic cholecystectomies were found: 182 women and 33 men. The median age in the population was 41 years. 73.02% resided in San Salvador. 92% of the patients were ASA I and II. 100% had criteria for laparoscopic cholecystectomy. 94.4% had social criteria for outpatient surgery. The surgery suspension rate was 10.48%. Of the surgeries performed: the conversion rate was 1.95%, due to adherence (3) and Mirizzi syndrome (1). The hospital admission rate was 15.12%, the most frequent cause was intraoperative complications. There were no readmissions or mortality. In conclusion, the ambulatory laparoscopic cholecystectomy program at the HNR is a safe procedure

Assuntos