title: glmS of Thermus thermophilus HB8: an essential gene for cell-wall synthesis identified immediately upstream of the S-layer gene.
abstract: A 30 kbp chromosomal region containing the S-layer gene (slpA) from Thermus thermophilus HB8 was cloned from a lambda phage gene library. DNA sequence analysis of the region upstream to the slpA gene revealed the presence of an open reading frame (ORF) which coded for a 604-amino-acid protein highly homologous to the glucosamine-6-P synthases (EC 2.6.1.16) of both prokaryotic and eukaryotic origin. The identification of this ORF as the glucosamine-6-P synthase gene from T. thermophilus (glmSth) has been carried out using three different strategies: (i) complementation of an Escherichia coli glmS mutant; (ii) in vivo insertional inactivation of the gene; and (iii) in vitro synthesis of glucosamine-6-P at 60 degrees C by a cytoplasmic extract of an overproducing E. coli strain. The glmSth gene is transcribed divergently from slpA in a 2.0 kb mRNA which probably also includes a tryptophan tRNA gene (trpTth) identified at its 3' extreme. As the products of both the glmSth and the slpA genes are main components of the cell envelope of T. thermophilus, their unusual clustering in the chromosome could be related to the existence of specific mechanisms for their coordinate expression.
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001426:Bacterial Proteins; D001483:Base Sequence; D002473:Cell Wall / Q000378:metabolism; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics*; D005945:Glutamine-Fructose-6-Phosphate Transaminase (Isomerizing) / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D012329:RNA, Bacterial / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D016963:Thermus thermophilus / Q000201:enzymology / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics
chemical_list: D000596:Amino Acids; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; C070683:surface layer protein A, Bacteria; D005945:Glutamine-Fructose-6-Phosphate Transaminase (Isomerizing)