Relaxed control of sugar utilization in Lactobacillus brevis

• DOI: 10.1099/mic.0.024653-0
• Publication Date: 2009-03-31T07:52:51Z
• Authors: Jae-Han Kim; Sharon P. Shoemaker; David A. Mills
• Keywords: Lactobacillus brevis; Xylose isomerase

Prioritization of sugar consumption is a common theme in bacterial growth and problem for complete utilization five six carbon sugars derived from lignocellulose. Growth studies show that Lactobacillus brevis simultaneously consumes numerous sources appears to lack normal hierarchical control carbohydrate utilization. Analysis several independent L. isolates indicated co-utilization xylose glucose trait this species. Moreover, carbohydrates can be used as single source are utilized with glucose. the proteome cells grown on glucose, or glucose/xylose mixture revealed constitutive expression enzymes heterofermentative pathway. In addition, fermentative mass balances between mixed inputs end-products both metabolized through Proteomic mRNA analyses genes xyl operon were expressed mixtures but not those alone. However, level XylA XylB proteins was reduced 2.7-fold observed solely xylose. These results suggest regulation stringently controlled seen other lactic acid bacteria, where catabolite repression operates prioritize more rigorously.