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Diversity of both the cultivable protease-producing bacteria and bacterial extracellular proteases in the coastal sediments of King George Island, Antarctica.

ABSTRACT: Protease-producing bacteria play a vital role in degrading sedimentary organic nitrogen. However, the diversity of these bacteria and their extracellular proteases in most regions remain unknown. In this paper, the diversity of the cultivable protease-producing bacteria and of bacterial extracellular proteases in the sediments of Maxwell Bay, King George Island, Antarctica was investigated. The cultivable protease-producing bacteria reached 10(5) cells/g in all 8 sediment samples. The cultivated protease-producing bacteria were mainly affiliated with the phyla Actinobacteria, Firmicutes, Bacteroidetes, and Proteobacteria, and the predominant genera were Bacillus (22.9%), Flavobacterium (21.0%) and Lacinutrix (16.2%). Among these strains, Pseudoalteromonas and Flavobacteria showed relatively high protease production. Inhibitor analysis showed that nearly all the extracellular proteases from the bacteria were serine proteases or metalloproteases. These results begin to address the diversity of protease-producing bacteria and bacterial extracellular proteases in the sediments of the Antarctic Sea.

SUBMITTER: Zhou MY

PROVIDER: S-EPMC3817139 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Diversity of both the cultivable protease-producing bacteria and bacterial extracellular proteases in the coastal sediments of King George Island, Antarctica.

Zhou Ming-Yang MY Wang Guang-Long GL Li Dan D Zhao Dian-Li DL Qin Qi-Long QL Chen Xiu-Lan XL Chen Bo B Zhou Bai-Cheng BC Zhang Xi-Ying XY Zhang Yu-Zhong YZ

PloS one 20131104 11

Protease-producing bacteria play a vital role in degrading sedimentary organic nitrogen. However, the diversity of these bacteria and their extracellular proteases in most regions remain unknown. In this paper, the diversity of the cultivable protease-producing bacteria and of bacterial extracellular proteases in the sediments of Maxwell Bay, King George Island, Antarctica was investigated. The cultivable protease-producing bacteria reached 10(5) cells/g in all 8 sediment samples. The cultivated ...[more]

PMID: 24223990

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Dataset Information

Diversity of both the cultivable protease-producing bacteria and bacterial extracellular proteases in the coastal sediments of King George Island, Antarctica.

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Diversity of both the cultivable protease-producing bacteria and bacterial extracellular proteases in the coastal sediments of King George Island, Antarctica.

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