Staphylococcus simulans biovar staphylolyticus lysostaphin efficiently cleaves aureus cell walls. The protein is in late clinical trials as a topical anti-staphylococcal agent, and can be used to prevent staphylococcal growth on artificial surfaces. Moreover, the gene has been both stably engineered into virally delivered mice or livestock obtain resistance against staphylococci. Here, we report first crystal structure of mature two structures its isolated catalytic domain at 3.5, 1.78 1.26...

Abstract Staphylococcus simulans lysostaphin cleaves pentaglycine cross-bridges between stem peptides in the peptidoglycan of susceptible staphylococci, including S. aureus . This enzyme consists an N-terminal catalytic domain and a cell wall binding (SH3b), which anchors protein to peptidoglycan. Although structures SH3bs from are available, modes these domains still unclear. We have solved crystal structure SH3b complex with peptide representing cross-bridge. The identifies groove β1 β2...

Abstract LytM is a Staphylococcus aureus autolysin and homologue of the S. simulans lysostaphin. Both enzymes are members M23 metallopeptidase family (MEROPS) comprising primarily bacterial peptidoglycan hydrolases. occurs naturally in latent form, but can be activated by cleavage an inhibitory N-terminal proregion. Here, we present 1.45 Å crystal structure catalytic domain with transition state analogue, tetraglycine phosphinate, bound active site. In electron density, site peptidase,...

Staphylococcus aureus remains one of the most common and at same time dangerous bacteria. The spreading antibiotic resistance calls for intensification research on staphylococcal physiology development new strategies combating this threatening pathogen. We have engineered chimeric enzymes comprising enzymatically active domain (EAD) autolysin LytM from S. cell wall binding (CBD) bacteriocin lysostaphin. They display potent activity in extended environmental conditions. Our results exemplify...

Peptidoglycan (PG) hydrolases, due to their crucial role in the metabolism of bacterial cell wall (CW), are increasingly being considered suitable targets for therapies, and a potent alternative conventional antibiotics. In light contradictory data reported, detailed mechanism regulation enzymes activity based on electrostatic interactions between hydrolase molecule CW surface remains unknown. Here, we report comprehensive study this phenomenon using as model two novel PG SpM23_A, SpM23_B,...

Studies of arginase expression and activity in guinea pig alveolar macrophages during Trichinella spiralis infection, prompted by earlier observation innate lung response to the parasite, showed express both protein type I. In cultured part enzyme was found be always released extracellular medium. Whereas BCG vivo treatment, alone or preceded T. stimulated activity, infection affected distribution between intracellular fractions, properties (K(m) V(max)), rather than total (intracellular +...

Bacterial peptidoglycan hydrolases play an essential role in cell wall metabolism during bacterial growth, division, and elongation (autolysins) or the elimination of closely related species from same ecological niche (bacteriocins). Most studies concerning present Gram-positive bacteria have focused on clinically relevant Staphylococcus aureus model organism Bacillus subtilis , while knowledge relating to other remains limited. Here, we report two new M23 family metallopeptidases derived...

The spread of antimicrobial resistance requires the development novel strategies to combat superbugs. Bacteriolytic enzymes (enzybiotics) that selectively eliminate pathogenic bacteria, including resistant strains and biofilms, are attractive alternatives antibiotics, also as a component new generation wound dressings. AuresinePlus is novel, engineered enzybiotic effective against Staphylococcus aureus—one most common found in infected wounds with very high prevalence antibiotic resistance....

The best-characterized members of the M23 family are glycyl-glycine hydrolases, such as lysostaphin (Lss) from Staphylococcus simulans or LytM aureus. Recently, enzymes with broad specificities were reported, EnpACD Enterococcus faecalis, that cleaves D,L peptide bond between stem and a cross-bridge. Previously, activity was demonstrated only on isolated peptidoglycan fragments. Herein we report conditions in which lyses bacterial cells live very high efficiency demonstrating great...

Staphylococcus spp. are Gram-positive bacteria that can be opportunistic pathogens capable of causing life-threatening infections. aureus, the most harmful species among them produces heat-resistant endotoxins, which cause food intoxications. Staphylococci may form biofilms on food-processing surfaces and become more resistant to routinely used antimicrobials. The bacteriolytic enzymes Auresine AuresinePlus, both derived from S. aureus LytM autolysin engineered catalytic domain, were tested...

The persistent expression of thymidylate synthase activity has previously been demonstrated not only in adult forms, but also non-developing muscle larvae Trichinella spiralis and T. pseudospiralis, pointing to an unusual pattern cell cycle regulation, prompting further studies on the developmental gene expression. enzyme cDNA was cloned sequencedNucleotide sequence data reported this paper are available GenBank™, EMBL DDBJ databases under Accession number AF162691., allowing...

Summary In order to assess immunological response, induced in guinea‐pig lungs by Trichinella spiralis, cellular infiltration into pulmonary alveolar space and production of NO macrophages obtained from bronchoalveolar lavage fluid (BALF), as well accumulation nitric oxide (NO) metabolites BALF serum, were evaluated during the early period primary T. spiralis infection (from 4th 8th on 14th day after oral administration larvae) 6th secondary infection. Primary caused increased lymphocytes,...

Mouse thymidylate synthase R209K (a mutation corresponding to R218K in Lactobacillus casei), overexpressed synthase-deficient Escherichia coli strain, was poorly soluble and with only feeble enzyme activity. The mutated protein, incubated FdUMP N(5,10)-methylenetetrahydrofolate, did not form a complex stable under conditions of SDS/polyacrylamide gel electrophoresis. reaction catalyzed by the (studied crude extract), compared that purified wild-type recombinant mouse synthase, showed K(m)...

Thymidylate synthase is a housekeeping gene, designated ancient due to its role in DNA synthesis and ubiquitous phyletic distribution. The genomic sequences were characterized coding for thymidylate two species of the genus Trichinella, an encapsulating T. spiralis non-encapsulating pseudospiralis.Based on sequence parasitic nematode Trichinella cDNA, PCR techniques employed.Each respective gene structures encompassed 6 exons 5 introns located conserved sites. Comparison with corresponding...

ABSTRACT Antimicrobial resistance poses a significant global threat, reaching dangerously high levels as reported by the World Health Organization. The emergence and rapid spread of new mechanisms, coupled with absence effective treatments in recent decades, have led to thousands deaths annually from infections caused drug-resistant microorganisms. Consequently, there is an urgent need for development compounds capable combating antibiotic-resistant bacteria. A promising class molecules...

Mikroorganizmy na naszej skórze tworzą swoje mikroświaty, żyjąc z nami w symbiozie.

The microorganisms on our skin create their own micro-worlds, living in symbiosis with us.

The effects of cyclosporin A (CsA), a potent immunosuppressive drug with antiparasitic activity, on the innate immunological response in guinea pig lungs during an early period (6th and 14th days) after T. spiralis infection were studied. CsA treatment spiralis-infected pigs caused significant attenuation by decreasing lymphocyte infiltration into pulmonary alveolar space, inhibiting macrophage superoxide anion production lowering both NO metabolites measured bronchoalveolar lavage fluid...