title: Analysis of the 5' portion of the type 19A capsule locus identifies two classes of cpsC, cpsD, and cpsE genes in Streptococcus pneumoniae.
abstract: Analysis of the sequence data obtained from the 5' portion of the Streptococcus pneumoniae type 19A capsular polysaccharide biosynthesis locus (cps19a) revealed that the first seven genes are homologous to the first seven genes in the type 19F (cps19f) locus. The former genes were designated cps19aA to -G and were 70 to 90% identical to their cps19f counterparts. Southern hybridization analysis of the cps loci from various S. pneumoniae serotypes with probes specific for the cps19aC, cps19aD, and cps19aE genes indicated a hybridization pattern complementary to that previously reported for cps19fC, cps19fD, and cps19fE. That is, all serotypes tested contained high-stringency homologues of either the cps19aC to -E genes or the cps19fC to -E genes, but not both. On this basis S. pneumoniae cps loci can be divided into two distinct classes. Long-range PCR was used to amplify the cps regions between cpsB and aliA from a variety of pneumococcal serotypes. Direct sequencing of the 5' end of these PCR products, and phylogenetic analysis of the sequence data, confirmed the presence of the two distinct classes of cpsC. Whereas members within one class are greater than 95% identical to each other, the DNA sequence identity between the two classes is only approximately 70%.
authors.affiliation: Molecular Microbiology Unit, Women's and Children's Hospital, North Adelaide, South Australia 5006.
authors.forename: J K
authors.initials: JK
authors.lastname: Morona
authors.forename: R
authors.initials: R
authors.lastname: Morona
authors.forename: J C
authors.initials: JC
authors.lastname: Paton
mesh_terms: D016667:Bacterial Capsules / Q000096:biosynthesis*; D001426:Bacterial Proteins; D001483:Base Sequence; D015139:Blotting, Southern; D005700:Galactosyltransferases / Q000737:chemistry / Q000235:genetics*; D005798:Genes, Bacterial / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016366:Open Reading Frames / Q000235:genetics; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D013296:Streptococcus pneumoniae / Q000145:classification* / Q000201:enzymology / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; C082664:CpsD protein, bacteria; D005700:Galactosyltransferases