Novel cold-adaptive Penicillium strain FS010 secreting thermo-labile xylanase isolated from Yellow Sea.
A novel cold-adaptive xylanolytic Penicillium strain FS010 was isolated from Yellow sea sediments. The marine fungus grew well from 4 to 20 degrees; a lower (0 degrees) or higher (37 degrees) temperature limits its growth. The strain was identified as Penicillium chrysogenum. Compared with mesophilic P. chrysogenum, the cold-adaptive fungus secreted the cold-active xylanase (XYL) showing high hydrolytic activities at low temperature (2-15 degrees) and high sensitivity to high temperature (>50 degrees). The XYL gene was isolated from the cold-adaptive P. chrysogenum FS010 and designated as xyl. The deduced amino acid sequence of the protein encoded by xyl showed high homology with the sequence of glycoside hydrolase family 10. The gene was subcloned into an expression vector pGEX-4T-1 and the encoded protein was overexpressed as a fusion protein with glutathione-S-transferase in Escherichia coli BL21. The expression product was purified and subjected to enzymatic characterization. The optimal temperature and pH for recombinant XYL was 25 degrees and 5.5, respectively. Recombinant XYL showed nearly 80% of its maximal activity at 4 degrees and was active in the pH range 3.0-9.5.
State Key Laboratory of Microbial Technology, University of Shandong, Jinan 250100, China.
Yun-Hua
YH
Hou
Tian-Hong
TH
Wang
Hao
H
Long
Hui-Yuan
HY
Zhu
D000222:Adaptation, Physiological; D001483:Base Sequence; D003001:Cloning, Molecular; D003080:Cold Temperature; D004591:Electrophoresis, Polyacrylamide Gel; D043364:Endo-1,4-beta Xylanases / Q000378:metabolism*; D004795:Enzyme Stability; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D015966:Gene Expression Regulation, Fungal; D005822:Genetic Vectors; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D009792:Oceans and Seas; D010407:Penicillium / Q000201:enzymology* / Q000254:growth & development; D010408:Penicillium chrysogenum / Q000201:enzymology / Q000254:growth & development; D011993:Recombinant Fusion Proteins / Q000235:genetics; D013696:Temperature; D013997:Time Factors
D011993:Recombinant Fusion Proteins; D005982:Glutathione Transferase; D043364:Endo-1,4-beta Xylanases