Kim Duwoon, Baik Keun Sik, Park Seong Chan, Kim Seon-Jun, Shin Tai-Sun, Jung Sung-Joo, Oh Myung-Joo, Seong Chi Nam
Division of Food Science and Aqualife Medicine, Chonnam National University, Yeosu, Republic of Korea.
J Ind Microbiol Biotechnol. 2009 Nov;36(11):1375-82. doi: 10.1007/s10295-009-0623-y. Epub 2009 Jul 29.
Pseudoalteromonas sp. NO3 was isolated from the hemolymph of diseased sea squirts (Halocynthia rorentzi) with symptoms of soft tunic syndrome. The strain was found to produce an extracellular cellulase (CelY) that consisted of a 1,476 bp open reading frame encoding 491 amino acid residues with an approximate molecular mass of 52 kDa. Homologies of the deduced amino acid sequence of celY with the products of the celA, celX, celG and cel5Z genes were 92.6, 93.3, 92.6, and 59.1%, respectively. Additionally, CelY had 50-80% remnant catalytic activity at temperatures of 10-20 degrees C. Highest carboxymethyl cellulose (CMC) hydrolysis was observed at pH 8.0 and 40 degrees C. CMC activity was determined by zymogram active staining and different degraded product profiles for CelY were obtained when cellotetraose, cellopentaose, and CMC were used as substrates. This study identified a transglycosylation activity in CelY that allows the enzyme to digest G4 to G2 and G3 without the production of G1.
假交替单胞菌NO3是从患有软囊综合征症状的患病海鞘（Halocynthia rorentzi）的血淋巴中分离出来的。该菌株被发现能产生一种细胞外纤维素酶（CelY），它由一个1476 bp的开放阅读框组成，编码491个氨基酸残基，分子量约为52 kDa。celY推导的氨基酸序列与celA、celX、celG和cel5Z基因产物的同源性分别为92.6%、93.3%、92.6%和59.1%。此外，CelY在10至20摄氏度的温度下具有50 - 80%的残余催化活性。在pH 8.0和40摄氏度时观察到最高的羧甲基纤维素（CMC）水解。通过酶谱活性染色测定CMC活性，当以纤维四糖、纤维五糖和CMC作为底物时，获得了CelY不同的降解产物谱。本研究确定了CelY中的一种转糖基化活性，该活性使该酶能够消化G4生成G2和G3，而不产生G1。
