Sialylation of bacterial capsules has been proposed as an important virulence factor for several species of encapsulated pathogens, including group B Streptococcus. We have constructed a transposon mutant strain of type III group B Streptococcus that expresses a capsular polysaccharide differing from the wild type only in that the mutant strain's capsule lacks sialic acid. The mutant polysaccha...

Group A streptococcus (GAS) is synonymous with Streptococcus pyogenes, the only species within this group of β-hemolytic streptococci. GAS is one of the leading pathogenic bacteria that infects children and adolescents, and is associated with a wide spectrum of infections and disease states. Worldwide, there are estimated to be >600 million cases of GAS pharyngitis (“strep throat”) and >100 mil...

in the present study, variation among different bacterial strains was observed in the plaques of tobacco chewers (tc) as compared to those from normal persons (non tobacco chewers) (ntc). bacterial strain j1 (dominant in the plaques of ntc) did not initiate the process of adhesion (biofilm formation) until it appeared to have reached a required population density necessary for the production of...

abstract background: streptococcus mutans in the oral cavities sable to produce mutacin (bacteriocin-like substances) with antibiotic properties. the aim of this study was to investigate the frequency and expression of genes encoding mutacins typei, ii, iii and iv and also two of 8 genes in a cluster encoding the putative bacteriocins, the designated bsm 283, bsm 299, bsm 423, bsm 1889c, bsm 18...

objective: bioactive glass 45s5 is a surface reactive glass-ceramic biomaterial, developed in 1969. bag 45s5 with particle size of 20-60 nm has the ability of bone regeneration, broad spectrum antibacterial effect, repairs and replaces diseased or damaged bone. the aim of this study was to evaluate the antibacterial activity and determine mic and mbc values of nano-bag45s5 on streptococcus muta...

background and objectives: the development of molecular biological techniques provide a method for direct detection and identification of pathogens. this study attempted to compare bacterial culture and pcr to detect s. agalactiae in cattle milk samples. the pcr method was based on using primers v1 and v2 derived from the 16s rrna gene. materials and methods: one hundred milk samples were colle...

conclusions performing only culture method led to missed false negative carriers. therefore, it is recommended that both the pcr assay and conventional culture method be routinely performed to detect gbs in pregnant women accurately. pcr diagnosis demonstrated a shorter turnaround time when compared with the time consuming culture method. results the prevalence of gbs in the 203 collected sampl...

background: selective antibody deficiency with normal immunoglobulins (sadni) may be identified as part of distinct primary or secondary immunodeficiency disorders. the clinical manifestations include recurrent, often severe or prolonged, upper or lower respiratory tract infections. objectives: to evaluate sadni in patients with recurrent sinopulmonary infections and its relation to igg subclas...

background: group b streptococcus is regarded as a potential factor for adverse outcomes of pregnancy such as preterm birth. objective: to study the association of maternal vaginal colonization with group b streptococcus (gbs) and preterm labor. materials and methods: from april 2005 to may 2006, vaginal culture for gbs were conducted in 101 laboring women with a gestational age of 24-37 weeks ...