Document Detail

Glucokinase contributes to glucose phosphorylation in D-lactic acid production by Sporolactobacillus inulinus Y2-8.
MedLine Citation:
PMID:  22892885     Owner:  NLM     Status:  MEDLINE    
Sporolactobacillus inulinus, a homofermentative lactic acid bacterium, is a species capable of efficient industrial D-lactic acid production from glucose. Glucose phosphorylation is the key step of glucose metabolism, and fine-tuned expression of which can improve D-lactic acid production. During growth on high-concentration glucose, a fast induction of high glucokinase (GLK) activity was observed, and paralleled the patterns of glucose consumption and D-lactic acid accumulation, while phosphoenolpyruvate phosphotransferase system (PTS) activity was completely repressed. The transmembrane proton gradient of 1.3-1.5 units was expected to generate a large proton motive force to the uptake of glucose. This suggests that the GLK pathway is the major route for glucose utilization, with the uptake of glucose through PTS-independent transport systems and phosphorylation of glucose by GLK in S. inulinus D-lactic acid production. The gene encoding GLK was cloned from S. inulinus and expressed in Escherichia coli. The amino acid sequence revealed significant similarity to GLK sequences from Bacillaceae. The recombinant GLK was purified and shown to be a homodimer with a subunit molecular mass of 34.5 kDa. Strikingly, it demonstrated an unusual broad substrate specificity, catalyzing phosphorylation of 2-deoxyglucose, mannitol, maltose, galactose and glucosamine, in addition to glucose. This report documented the key step concerning glucose phosphorylation of S. inulinus, which will help to understand the regulation of glucose metabolism and D-lactic acid production.
Lu Zheng; Zhongzhong Bai; Tingting Xu; Bingfang He
Related Documents :
4986835 - Biosynthesis of phytoquinones. homogentisic acid: a precursor of plastoquinones, tocoph...
7253965 - Transformation of bile acids by mixed microbial cultures from human feces and bile acid...
4033365 - The di- and triesters of the lipids of steer and human meibomian glands.
4245 - Physico-chemical and immunological properties of acid alpha-glucosidase from various hu...
20932325 - Identification of differences in human and great ape phytanic acid metabolism that coul...
16323755 - Lipid composition and contaminants in farmed and wild salmon.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2012-08-15
Journal Detail:
Title:  Journal of industrial microbiology & biotechnology     Volume:  39     ISSN:  1476-5535     ISO Abbreviation:  J. Ind. Microbiol. Biotechnol.     Publication Date:  2012 Nov 
Date Detail:
Created Date:  2012-10-23     Completed Date:  2013-07-22     Revised Date:  2013-11-15    
Medline Journal Info:
Nlm Unique ID:  9705544     Medline TA:  J Ind Microbiol Biotechnol     Country:  England    
Other Details:
Languages:  eng     Pagination:  1685-92     Citation Subset:  IM    
College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing 211816, China.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Bacillaceae / genetics
Bacillales / classification,  metabolism*
Biological Transport / genetics
Escherichia coli / genetics,  metabolism
Glucokinase / genetics,  metabolism*
Glucose / metabolism*
Lactic Acid / biosynthesis*,  metabolism
Phosphoenolpyruvate Sugar Phosphotransferase System
Substrate Specificity
Reg. No./Substance:
50-21-5/Lactic Acid; 50-99-7/Glucose; EC 2.7.1.-/Phosphoenolpyruvate Sugar Phosphotransferase System; EC

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Genetic characterization and construction of an auxotrophic strain of Saccharomyces cerevisiae JP1, ...
Next Document:  Construction and application of an Escherichia coli bioreporter for aniline and chloroaniline detect...