AME 69:33-46 (2013)  -  DOI: https://doi.org/10.3354/ame01618

Succession of protease activity in seawater and bacterial isolates during starvation in a mesocosm experiment

Chui Wei Bong1,2,3,*, Yumiko Obayashi1,4, Satoru Suzuki1

1Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama 790-8577, Japan
2Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
3Institute of Ocean and Earth Sciences (IOES), University of Malaya, 50603 Kuala Lumpur, Malaysia
4Faculty of Engineering, Yokohama National University, Yokohama 240-8501, Japan

ABSTRACT: Protein biodegradation in the marine environment is caused by proteases derived from various organisms, including bacteria, which are considered to be a major source of these enzymes. We investigated the succession of bacterial proteases in seawater to determine the variation in protease activity over time. The potential activities of proteolytic enzymes in stored seawater and isolated bacteria were studied using 19 different synthetic oligopeptide substrates for aminopeptidase, trypsin, chymotrypsin and elastase. In time-course experiments carried out over 112 d, aminopeptidase activity increased, whereas trypsin activity decreased over time. Aminopeptidase activity was mainly found in unfiltered seawater containing bacterial cells, whereas trypsin activity was mainly found in 0.2 ┬Ám seawater filtrates. Individual bacterial isolates showed different proteolytic properties but all exhibited aminopeptidase activity. Members of the Gammaproteobacteria and Bacteroidetes showed high trypsin and chymotrypsin activities. Based on these results, we conclude that protein degradation in seawater occurs via the combined action of various bacterial proteases.


KEY WORDS: Bacterial protease · Aminopeptidase · Trypsin · Cell-associated enzymes · Dissolved fraction · Seawater


Full text in pdf format 
Cite this article as: Bong CW, Obayashi Y, Suzuki S (2013) Succession of protease activity in seawater and bacterial isolates during starvation in a mesocosm experiment. Aquat Microb Ecol 69:33-46. https://doi.org/10.3354/ame01618

Export citation
Mail this link - Contents Mailing Lists - RSS
- -