title: Expression of citrate permease gene of plasmid pCM1 isolated from Lactococcus lactis subsp. lactis biovar diacetylactis NIAI N-7 in Lactobacillus casei L-49-4.
abstract: Recombinant vector pJLECit (8,232 bp) was constructed using citrate permease gene contained in the 3,919-bp fragment of plasmid pCM1 (8,280 bp) isolated from Lactococcus lactis subsp. lactis biovar diacetylactis NIAI N-7, repA and ori from pLU1, and pMB1 ori and the erythromycin resistance gene from pJIR418. Lactobacillus casei L-49-4 (plasmid-free mutant of strain L-49) harboring the constructed pJLECit converted citrate into diacetyl/acetoin. Citrate uptake rate of resting cells was the highest at pH 5.5 and 10 mM citrate concentration. Diacetyl formation activity by the cell-free extracts of Lb. casei L-49-4 (pJLECit) grown in de Man-Rogosa-Sharpe (MRS) broth was higher than that of cells grown in MRS broth without citrate. On the other hand, diacetyl reductase activity of cells grown in MRS broth was lower than that of cells grown in MRS broth without citrate.
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, Tsushima, Okayama, 700-8530, Japan.
authors.forename: Hwa-Yong
authors.initials: HY
authors.lastname: An
authors.forename: Harutoshi
authors.initials: H
authors.lastname: Tsuda
authors.forename: Taku
authors.initials: T
authors.lastname: Miyamoto
mesh_terms: D000093:Acetoin / Q000378:metabolism; D000094:Acetoin Dehydrogenase / Q000032:analysis; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D019343:Citric Acid / Q000378:metabolism; D003001:Cloning, Molecular; D003470:Culture Media; D004265:DNA Helicases / Q000235:genetics; D003931:Diacetyl / Q000378:metabolism; D015870:Gene Expression; D005822:Genetic Vectors; D006863:Hydrogen-Ion Concentration; D007780:Lacticaseibacillus casei / Q000235:genetics* / Q000378:metabolism; D013294:Lactococcus lactis / Q000201:enzymology* / Q000235:genetics; D008780:Methyltransferases / Q000235:genetics; D027361:Organic Anion Transporters / Q000096:biosynthesis* / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D027361:Organic Anion Transporters; D011994:Recombinant Proteins; D019343:Citric Acid; C065431:citP protein, Lactococcus lactis; D000093:Acetoin; D000094:Acetoin Dehydrogenase; C111078:ErmTR protein, bacteria; D008780:Methyltransferases; D004265:DNA Helicases; D003931:Diacetyl