Carbohydrase systems of Saccharophagus degradans degrading marine complex polysaccharides.

Saccharophagus degradans 2-40 is a γ-subgroup proteobacterium capable of using many of the complex polysaccharides found in the marine environment for growth. To utilize these complex polysaccharides, this bacterium produces a plethora of carbohydrases dedicated to the processing of a carbohydrate class. Aiding in the identification of the contributing genes and enzymes is the known genome sequence for this bacterium.

Hydrolytic and phosphorolytic metabolism of cellobiose by the marine aerobic bacterium Saccharophagus degradans 2-40T.

Saccharophagus degradans 2-40 is a marine gamma proteobacterium that can produce polyhydroxyalkanoates from lignocellulosic biomass using a complex cellulolytic system. This bacterium has been annotated to express three surface-associated β-glucosidases (Bgl3C, Ced3A, and Ced3B), two cytoplasmic β-glucosidases (Bgl1A and Bgl1B), and unusual for an aerobic bacterium, two cytoplasmic cellobiose/cellodextrin phosphorylases (Cep94A and Cep94B). Expression of the genes for each of the above enzymes was induced when cells were transferred into a medium containing Avicel as the major carbon source except for Bgl1B.

Lytic transglycosylase MltB of Escherichia coli and its role in recycling of peptidoglycan strands of bacterial cell wall.

The cell wall is an indispensable structure for the survival of bacteria and a target for antibiotics. Peptidoglycan is the major constituent of the cell wall, which is comprised of backbone repeats of N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM). A peptide stem is appended to the NAM unit, which in turn experiences cross-linking with a peptide from another peptidoglycan in the final steps of cell wall assembly.

Shared functional attributes between the mecA gene product of Staphylococcus sciuri and penicillin-binding protein 2a of methicillin-resistant Staphylococcus aureus.

The genome of Staphylococcus aureus is constantly in a state of flux, acquiring genes that enable the bacterium to maintain resistance in the face of antibiotic pressure. The acquisition of the mecA gene from an unknown origin imparted S. aureus with broad resistance to beta-lactam antibiotics, with the resultant strain designated as methicillin-resistant S.

Cytoplasmic-membrane anchoring of a class A beta-lactamase and its capacity in manifesting antibiotic resistance.

Bacterial beta-lactamases are the major causes of resistance to beta-lactam antibiotics. Three classes of these enzymes are believed to have evolved from ancestral penicillin-binding proteins (PBPs), enzymes responsible for bacterial cell wall biosynthesis. Both beta-lactamases and PBPs are able to efficiently form acyl-enzyme species with beta-lactam antibiotics.

The basis for resistance to beta-lactam antibiotics by penicillin-binding protein 2a of methicillin-resistant Staphylococcus aureus.

Penicillin-binding protein 2a (PBP2a) of Staphylococcus aureus is refractory to inhibition by available beta-lactam antibiotics, resulting in resistance to these antibiotics. The strains of S. aureus that have acquired the mecA gene for PBP2a are designated as methicillin-resistant S.

Synthetic peptidoglycan substrates for penicillin-binding protein 5 of Gram-negative bacteria.

The major constituent of the bacterial cell wall, peptidoglycan, is comprised of repeating units of N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM) with an appended peptide. Penicillin-binding proteins (PBPs) are involved in the final stages of bacterial cell wall assembly. Two activities for PBPs are the cross-linking of the cell wall, carried out by dd-transpeptidases, and the dd-peptidase activity, that removes the terminal d-Ala residue from peptidoglycan.

A mechanism-based inhibitor targeting the DD-transpeptidase activity of bacterial penicillin-binding proteins.

Penicillin-binding proteins (PBPs) are responsible for the final stages of bacterial cell wall assembly. These enzymes are targets of beta-lactam antibiotics. Two of the PBP activities include dd-transpeptidase and DD-carboxypeptidase activities, which carry out the cross-linking of the cell wall and trimming of the peptidoglycan, the major constituent of the cell wall, by an amino acid, respectively.

Mutational replacement of Leu-293 in the class C Enterobacter cloacae P99 beta-lactamase confers increased MIC of cefepime.

The class C beta-lactamase from Enterobacter cloacae P99 confers resistance to a wide range of broad-spectrum beta-lactams but not to the newer cephalosporin cefepime. Using PCR mutagenesis of the E. cloacae P99 ampC gene, we obtained a Leu-293-Pro mutant of the P99 beta-lactamase conferring a higher MIC of cefepime (MIC, 8 microg/ml, compared with 0.

[Antibacterial drug resistance of gram-negative agents causing urinary infections in female outpatients in Russia: results of multicenter study].

Aim: To investigate the spectrum of gram-negative agents causing acute and recurrent cystitis in outpatients and sensitivity of uropathogenic E. coli to antibacterial drugs; to compare drug resistance of uropathogenic E. coli isolated in Russia and other countries.

Detection of sequence variation in PCR-amplified fragments of omp2 gene from three species of the family Chlamydiaceae using agarose gel electrophoresis containing bisbenzimide-PEG.

A simple technique providing a means for rapid genetic differentiation of chlamydial strains is described. The technique is based on a single-step sequence-specific separation of PCR-amplified DNA fragments by electrophoresis in an agarose gel containing a DNA ligand - bisbenzimide-PEG. A hypervariable region at the 5' end of the omp2 gene of Chlamydiaceae species encoding the 60-kDa cysteine-rich outer membrane protein was selected as a target for PCR.