A peptide containing the CCHH motif, the putative zinc-binding sequence of influenza virus M1 protein, was found to bind zinc in a one-to-one complex with the characteristics of a typical zinc-binding peptide. Intact influenza virus also contained zinc and we show that this zinc is bound to the M1 protein in the virus. However, only a small proportion of M1 contained zinc: 4% in virus and 6 to ...

Many enveloped viruses encode a matrix protein. In the influenza A virus, the matrix protein M1 polymerizes into a rigid protein layer underneath the viral envelope to help enforce the shape and structural integrity of intact viruses. The influenza virus M1 is also known to mediate virus budding as well as the nuclear export of the viral nucleocapsids and their subsequent packaging into nascent...

Streptococcus pyogenes of the M1 serotype can cause streptococcal toxic shock syndrome and acute lung injury. Statins exert beneficial effects in septic patients although the mechanisms remain elusive. This study examined effects of simvastatin on M1 protein-provoked pulmonary inflammation and tissue injury. Male C57BL/6 mice were pretreated with simvastatin or a CXCR2 antagonist before M1 prot...

The Escherichia coli ribonuclease P (RNase P) has a protein component, termed C5, which acts as a cofactor for the catalytic M1 RNA subunit that processes the 5' leader sequence of precursor tRNA. Rpp29, a conserved protein subunit of human RNase P, can substitute for C5 protein in reconstitution assays of M1 RNA activity. To better understand the role of the former protein, we compare the mode...

Influenza A virus matrix protein (M1) is the most abundant conservative protein that regulates the replication, assembly and budding of the viral particles upon infection. Several host cell factors have been determined to interact with M1 possibly in regulating influenza virus replication. By yeast two-hybrid screening, the isomerase cyclophilin A (CypA) was identified to interact with the M1 p...

Group A Streptococcus (GAS) is a leading human pathogen producing a diverse array of infections from simple pharyngitis ("strep throat") to invasive conditions, including necrotizing fasciitis and toxic shock syndrome. The surface-anchored GAS M1 protein is a classical virulence factor that promotes phagocyte resistance and exaggerated inflammation by binding host fibrinogen (Fg) to form supram...

Streptococcus pyogenes of the M1 serotype can cause streptococcal toxic shock syndrome commonly associated with acute lung injury. The aim of the present study was to investigate the role of neutrophils and their secretion products in M1 protein-induced lung damage. The degranulation of neutrophils by M1 protein was studied in whole blood using marker analysis for individual granule subsets. In...

Surface-associated M protein is a major virulence factor in Streptococcus pyogenes which confers bacterial resistance to phagocytosis. However, many S. pyogenes strains also express additional structurally related so-called M-like proteins. The strain studied here is of the clinically important M1 serotype and expresses two structurally related surface proteins, the M1 protein and protein H. Mu...

The ability of a serotype M1 strain of Streptococcus pyogenes to efficiently invade A549 human lung epithelial cells was previously shown to be dependent on bacterial exposure to human or bovine serum proteins or synthetic peptides containing the sequence RGD. In this study, stimulation by invasion agonists was determined to be dependent on expression of the streptococcal cell surface protein, ...