title: Use of induction promoters to regulate hyaluronan synthase and UDP-glucose-6-dehydrogenase of Streptococcus zooepidemicus expression in Lactococcus lactis: a case study of the regulation mechanism of hyaluronic acid polymer.
abstract: OBJECTIVE
  To determine the effects of the ratios of hyaluronan synthase expression level to precursor sugar UDP-GlcA biosynthesis ability on the molecular weight (MW) of hyaluronic acid (HA) in recombinant Lactococcus lactis.
  
  
  RESULTS
  The genes szHasA (hyaluronan synthase gene) and szHasB (UDP-glucose-6-dehydrogenase gene) of Streptococcus zooepidemicus were introduced into L. lactis under the control of nisA promoter and lacA promoter respectively, resulting in a dual-plasmid controlled expression system. The effects of the ratios of hyaluronan synthase expression level to the precursor sugar UDP-GlcA biosynthesis ability under different induction concentration collocations with nisin and lactose on the MW of HA in recombinant L. lactis were determined. The results showed that the final weight-average molecular weight () of HA correlated with the relative ratios of HasA (hyaluronan synthase) expression level to the concentration of UDP-GlcA.
  
  
  CONCLUSIONS
  Regulating the relative ratios of HasA expression level to the precursor sugar biosynthesis ability was an efficient method to control the size of HA.
  
  
  CONCLUSIONS
  This study put forward a guide to establish an efficacious way to control the size of HA in fermentation.
authors.affiliation: Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Science, Shandong University, Jinan, Shandong, China.
authors.forename: J Z
authors.initials: JZ
authors.lastname: Sheng
authors.forename: P X
authors.initials: PX
authors.lastname: Ling
authors.forename: X Q
authors.initials: XQ
authors.lastname: Zhu
authors.forename: X P
authors.initials: XP
authors.lastname: Guo
authors.forename: T M
authors.initials: TM
authors.lastname: Zhang
authors.forename: Y L
authors.initials: YL
authors.lastname: He
authors.forename: F S
authors.initials: FS
authors.lastname: Wang
mesh_terms: D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects*; D005798:Genes, Bacterial / Q000187:drug effects; D014453:Glucuronosyltransferase / Q000235:genetics / Q000378:metabolism*; D000076002:Hyaluronan Synthases; D006820:Hyaluronic Acid / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D013294:Lactococcus lactis / Q000201:enzymology* / Q000235:genetics; D007785:Lactose / Q000494:pharmacology*; D008970:Molecular Weight; D009561:Nisin / Q000494:pharmacology*; D011401:Promoter Regions, Genetic; D012329:RNA, Bacterial / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D018502:Streptococcus equi / Q000201:enzymology* / Q000235:genetics; D014533:Uridine Diphosphate Glucose Dehydrogenase / Q000378:metabolism
chemical_list: D012329:RNA, Bacterial; D011994:Recombinant Proteins; D009561:Nisin; D006820:Hyaluronic Acid; D014533:Uridine Diphosphate Glucose Dehydrogenase; D014453:Glucuronosyltransferase; D000076002:Hyaluronan Synthases; D007785:Lactose