Improvement of alkaliphily of Bacillus alkaline xylanase by introducing amino acid substitutions both on catalytic cleft and protein surface.
Xylanase J (XynJ) from alkaliphilic Bacillus sp. 41M-1 is an alkaline xylanase. The crystal structure has been solved with XynJ. Improvement of the alkaliphily of XynJ was attempted by amino acid substitutions. Reinforcing the characteristic salt bridge in the catalytic cleft and introducing excess Arg residues on the protein surface shifted the optimum pH of the wild-type enzyme from 8.5 to 9.5.
Umemoto
Hirohito
H
Department of Bioengineering, Tokyo Institute of Technology, 4529 Nagatsuta, Midori-ku, Yokohama 226-8501, Japan.
Ihsanawati
Inami
Mayuko
M
Yatsunami
Rie
R
Fukui
Toshiaki
T
Kumasaka
Takashi
T
Tanaka
Nobuo
N
Nakamura
Satoshi
S
D019943:Amino Acid Substitution; D001407:Bacillus / Q000201:enzymology*; D020134:Catalytic Domain; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D009154:Mutation; D015202:Protein Engineering / Q000379:methods*; D013696:Temperature
D043364:Endo-1,4-beta Xylanases