Detection of Bacillus Amyloliquefaciens C1 Xylose Metabolism Related Enzyme

摘要

Lignocellulose resources and their hydrolyzate contain a large amount of mixed carbon sources such as glucose and xylose,but Bacillus is less effective in utilizing xylose.In most bacillus,xylose is first converted to xylulose by xylose isomerase(XI)and subsequently catalyzed by xylulokinase(XK)to form 5-phospho-xylulose to enter the pentose phosphate pathway.In this paper,a self-screening bacillus amyloliquefaciensC1 was studied and found that the bacteria can make good use of xylose as a carbon source for growth and metabolism.Usmg bacillus amyloliquefaciensFZB42 as a control to study in depth,two strams of bacteria were cultured in M9 containing lOg/L xylose,and when the culture time reached 44h,the strain C1 had almost completely consumed 10g/L of xylose,while the stram FZB42 Only consumed 2g/L of xylose.To understand the efficient use of xylose by C1 bacteria,we selected two of the most important enzymes in xylose metabolism,xylose isomerase and xylulokinase.The data showed that strain X1 and XKenzyme of strain C1 were higher than that of strain FZB42.Among them,C1 strain XI and XKenzyme could reach 0 200U/mg and 0.516U/mg respectively,which were 1.6 times and 2.4 times that ot FZB42 respectively.The results showed that X1,XK high enzyme is one of the reasons that bacillus amyloliquefaciens C1 can effectively utilize xylose.