Global transcriptional regulators that respond to specific environmental signals are crucial in bacterial pathogenesis. In the case of the Gram-positive pathogen Streptococcus pneumoniae (the pneumococcus), the sp1800 gene of the clinical isolate TIGR4 encodes a protein that exhibits homology to the Mga "stand-alone" response regulator of the group A Streptococcus. Such a pneumococcal protein w...

Streptococcus pneumoniae (pneumococcus) infection causes more than 1.6 million deaths worldwide. Pneumococcal growth is a prerequisite for its virulence and requires an appropriate supply of cellular energy. Adenylate kinases constitute a major family of enzymes that regulate cellular ATP levels. Some bacterial adenylate kinases (AdKs) are known to be critical for growth, but the physiological ...

In this study, we have explored the impact of ascorbic acid on the transcriptome of Streptococcus pneumoniae D39. The expression of several genes and operons, including the ula operon (which has been previously shown to be involved in ascorbic acid utilization), the AdcR regulon (which has been previously shown to be involved in zinc transport and virulence) and a PTS operon (which we denote he...

In Streptococcus pneumoniae expression of pyruvate oxidase (SpxB) peaks during the early growth phase, coincident with the time of natural competence. This study investigated whether SpxB influences parameters of competence, such as spontaneous transformation frequency, expression of competence genes, and DNA release. Knockout of the spxB gene in strain D39 abolished spontaneous transformation ...

Secondary bacterial infections are a leading cause of illness and death during epidemic and pandemic influenza. Experimental studies suggest a lethal synergism between influenza and certain bacteria, particularly Streptococcus pneumoniae, but the precise processes involved are unclear. To address the mechanisms and determine the influences of pathogen dose and strain on disease, we infected gro...

Streptococcus pneumoniae was shown to contain two types of superoxide dismutase, MnSOD and FeSOD. Levels of MnSOD increased during growth in an aerobic environment. The sodA gene, encoding MnSOD, of virulent S. pneumoniae type 2 strain D39 was inactivated to give mutant D39HY1. Aerobically, D39HY1 had a lower growth rate than the wild type and exhibited susceptibility to the redox-active compou...

Genome-wide screens have discovered a large set of essential genes in the opportunistic human pathogen Streptococcus pneumoniae However, the functions of many essential genes are still unknown, hampering vaccine development and drug discovery. Based on results from transposon sequencing (Tn-seq), we refined the list of essential genes in S. pneumoniae serotype 2 strain D39. Next, we created a k...

The vault particle, with a molecular weight of about 10 MDa, is the largest ribonucleoprotein that has been described. The X-ray structure of intact rat vault has been solved at a resolution of 3.5 Å [Tanaka et al. (2009), Science, 323, 384-388], showing an overall barrel-shaped architecture organized into two identical moieties, each consisting of 39 copies of the major vault protein (MVP). Th...

UNLABELLED Different strains of influenza virus are affecting a large number of people worldwide to combat with Influenza virus destruction, numerous synthetic antiviral medicines are available for influenza virus in the market. But still there was a need for the development of drug which will target all the strains of influenza virus. For this purpose conserved residues within the influenza vi...