title: GalR Acts as a Transcriptional Activator of galKT in the Presence of Galactose in Streptococcus pneumoniae.
abstract: We explored the regulatory mechanism of Leloir pathway genes in Streptococcus pneumoniae D39. Here, we demonstrate that the expression of galKT is galactose dependent. By microarray analysis and quantitative RT-PCR, we further show the role of the transcriptional regulator GalR, present upstream of galKT, as a transcriptional activator of galKT in the presence of galactose. Moreover, we predict a 19-bp regulatory site (5'-GATAGTTTAGTAAAATTTT-3') for the transcriptional regulator GalR in the promoter region of galK, which is also highly conserved in other streptococci. Growth comparison of D39 ΔgalK with the D39 wild type grown in the presence of galactose shows that galK is required for the proper growth of S. pneumoniae on galactose.
authors.affiliation: Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Afzal
authors.forename: Sulman
authors.initials: S
authors.lastname: Shafeeq
authors.forename: Irfan
authors.initials: I
authors.lastname: Manzoor
authors.forename: Oscar P
authors.initials: OP
authors.lastname: Kuipers
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism; D005686:Galactokinase / Q000235:genetics* / Q000378:metabolism; D005690:Galactose / Q000378:metabolism*; D005798:Genes, Bacterial; D005947:Glucose / Q000378:metabolism; D006601:Hexoses / Q000378:metabolism; D046228:Microarray Analysis / Q000379:methods; D008969:Molecular Sequence Data; D009154:Mutation; D009876:Operon; D011401:Promoter Regions, Genetic; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism; D013296:Streptococcus pneumoniae / Q000235:genetics* / Q000378:metabolism; D015533:Transcriptional Activation / Q000235:genetics*; D005694:UTP-Hexose-1-Phosphate Uridylyltransferase / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; C050993:Galactose repressor proteins; D006601:Hexoses; D012097:Repressor Proteins; D005686:Galactokinase; D005694:UTP-Hexose-1-Phosphate Uridylyltransferase; D005947:Glucose; C030192:tagatose; D005690:Galactose