Sunday, May 3, 2009
2-48
Isolation of cellulose and agarose-degrading Pseudoalteromonas sp. NO3 from Sea squirt, Halocynthia rorentzi
Duwoon Kim1, Sung-Joo Jung1, Jin-Kyung Song1, Keun-Sik Baik2, Seong-Chan Park2, Tai-Sun Shin1, Myung-Joo Oh1, Kyung-Ran Kim1, Hyung-Rak Kim3, and Chi-Nam Seong2. (1) Division of Food Science and Aqualife Medicine, Chonnam National University, San 96-1 Dundeok-Dong, Yeosu, 550-749, South Korea, (2) Department of Biology, Sunchon National University, 413 Joongang-Ro Maegok-Dong, Sunchon, 540-742, South Korea, (3) Department of Food Nutrition, Pukyung National University, 599-1 Daeyeon-Dong, Busan, 608-737, South Korea
Pseudoalteromonas sp. was reported for the main cause of mass mortality of sea squirt, Halocynthia rorentzi. Cellulose and agarose-degrading Pseudoalteromonas sp. NO3 was isolated from the tissue of abnormal Sea squirt. The highest agarase and cellulase activity was found in the culture supernatant of Pseudoalteromonas strain. The optimal pH and temperature of agarase and cellulase were determined by a reducing sugar assay, where the optimal pH of two enzymes was 8 and the optimal temperatures was 35°C. A thin layer chromatography (TLC) was used for the determination of agarose and cellulose hydrolysis reaction after incubating 200μl of substrates (agarose and carboxymethyl cellulose) and 25μl of culture supernatants (2.29mg/ml) at 35°C for 2hr. The presence of low molecular size of digested cellulose and agarose on the TLC plate indicated that Pseudoalteromonas strain secretes significant quantities of agarase and cellulase into extracellular environment. We showed high-throughput screening assay that agarase and cellulase activity can be directly measured using liquid cultures grown in a microtiter plate instead of separation or purification steps and is fast and easy to perform more adaptable for screening of a large number of samples.