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Lysylphosphatidylglycerol (LPG) is a basic phospholipid in which L-lysine from lysyl-tRNA is transferred to phosphatidylglycerol (PG). This study examined whether the Staphylococcus aureus mprF gene encodes LPG synthetase. A crude membrane fraction prepared from wild-type S. aureus cells had LPG synthetase activity that depended on PG and lysyl-tRNA,(More)
Some synthetic lipopeptides, in addition to native lipoproteins derived from both Gram-negative bacteria and mycoplasmas, are known to activate TLR2 (Toll-like receptor 2). However, the native lipoproteins inherent to Gram-positive bacteria, which function as TLR2 ligands, have not been characterized. Here, we have purified a native lipoprotein to(More)
The beta subunit of DNA polymerase III is essential for negative regulation of the initiator protein, DnaA. DnaA inactivation occurs through accelerated hydrolysis of ATP bound to DnaA; the resulting ADP-DnaA fails to initiate replication. The ability of beta subunit to promote DnaA inactivation depends on its assembly as a sliding clamp on DNA and must be(More)
We previously reported that the cvfA gene is a virulence regulatory gene in Staphylococcus aureus. Here, we identified a novel gene named sarZ that acts as a multicopy suppressor of decreased haemolysin production in the cvfA deletion mutant. The amount of sarZ transcripts was decreased in the cvfA mutant. The sarZ-deletion mutant produced less haemolysin(More)
Many bacteria accumulate granules of polyhydroxyalkanoate (PHA) within their cells, which confer resistance to nutritional depletion and other environmental stresses. Here, we report an unexpected involvement of the bacterial endocellular storage polymer, PHA, in an insect-bacterium symbiotic association. The bean bug Riptortus pedestris harbors a(More)
Wall teichoic acid (WTA) of Staphylococcus aureus is a major cell envelope-associated glycopolymer that is a key molecule in promoting colonization during S. aureus infection. The complement system plays a key role in the opsonization and clearance of pathogens. We recently reported that S. aureus WTA functions as a ligand of human serum mannose-binding(More)
OBJECTIVES The purpose of this study was to investigate the serological risk factors for development of adult T-cell leukemia/lymphoma (ATL) among human T-cell lymphotropic virus type-I (HTLV-I) carriers. METHODS A nested case-control study was performed. The source population comprised 23,922 subjects who had either visited the outpatient clinic or who(More)
The biochemical characterization of novel antimicrobial peptides (AMPs) and the determination of ligand molecules that induce AMP production are essential for understanding the host innate immune response in insects. Here, we purified a new 14-kDa AMP, named tenecin 4, from the larval hemolymph of the beetle Tenebrio molitor. Tenecin 4 contains 14% glycine(More)
DnaA protein activity, the initiator of chromosomal DNA replication in bacteria, is regulated by acidic phospholipids such as phosphatidylglycerol (PG) or cardiolipin (CL) via facilitation of the exchange reaction of bound adenine nucleotide. Total lipid isolated from exponentially growing Staphylococcus aureus cells facilitated the release of ATP bound to(More)
Pathogenic bacteria mitigate host immunity to establish infections, but the mechanism of this bacterial action has not been fully elucidated. To search for cell wall components that modulate innate immune responses in host organisms, we examined Staphylococcus aureus mutants, which were deficient in components of the cell wall, for pathogenicity in(More)