RESUMO
This study demonstrated that the bacteria could adsorb Fe3+ and reduce Fe3+ to Fe2+. Iron had significant bacteriostatic effects, which were directly proportional to the iron concentration and under the influence of pH and chelator. It presumed that the inhibition of Fe3+ acts through the formation of hydroxyl free radicals.
Assuntos
Antibacterianos/análise , Ferrobactérias/análise , Íons/análise , Quelantes de Ferro/análise , Sideróforos/análise , Métodos , MétodosRESUMO
An orange-pigmented, Gram-negative, nonmotile, strictly aerobic and oxidase- and catalase-positive bacterium (SM-A87(T)) was isolated from the deep-sea sediment of the southern Okinawa Trough area. The main fatty acids were i15 : 0, i17 : 0 3OH, i15 : 1 G, i17 : 1 omega 9c, 15 : 0, i15 : 0 3OH and summed feature 3 (comprising i-15 : 0 2OH and/or 16 : 1 omega 7c). MK-6 was the predominant respiratory quinone. DNA G+C content was 35.8 mol%. Flexirubin-type pigments were absent. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain SM-A87(T) formed a distinct lineage within the family Flavobacteriaceae, with <93% sequence similarity to the nearest strain of genus Salegentibacter. Moreover, strain SM-A87(T) could be distinguished from the nearest phylogenetic neighbors by a number of chemotaxonomic and phenotypic properties. On the basis of polyphasic analyses, it is proposed that strain SM-A87(T) be classified in a novel genus and a new species in the family Flavobacteriaceae, designated Wangia profunda gen. nov., sp. nov. The type strain is SM-A87(T) (CCTCC AB 206139(T)=DSM 18752).
Assuntos
Flavobacteriaceae/classificação , Flavobacteriaceae/isolamento & purificação , Sedimentos Geológicos/microbiologia , Água do Mar/microbiologia , Aerobiose , Catalase/biossíntese , China , DNA Bacteriano/química , DNA Bacteriano/genética , Ácidos Graxos/análise , Flavobacteriaceae/química , Flavobacteriaceae/fisiologia , Genes de RNAr/genética , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Oxirredutases/biossíntese , Fenótipo , Filogenia , Pigmentos Biológicos/biossíntese , Quinonas/análise , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido NucleicoRESUMO
The evolutionary distances of the 16S rDNA sequences in cellulolytic myxobacteria are less than 3%, which units all the strains into a single genus, Sorangium. The size of myxospores and the shape of sporangioles, rather than fruiting body colors or swarm morphologies are consistent with the changes of the 16S rDNA sequences. It is suggested that there are at least two species in the genus Sorangium: one includes strains with small myxospores and spherical sporangioles, and the color of the fruiting bodies is normally orange or brown, though sometimes yellow or black. The second species has large myxospores, polyhedral sporangioles with many inter-cystic substrates, and normally deep brown to black color.