Search results for "Coccus"
showing 10 items of 1002 documents
The hemagglutinin of Staphylococcus saprophyticus is a major adhesin for uroepithelial cells.
1996
The 160-kDa hemagglutinin of Staphylococcus saprophyticus also serves as a fibronectin-binding protein, and the two activities may be present on different parts of the molecule. Bacteria expressing the 160-kDa hemagglutinin bound in large numbers to histological sections of human ureters, whereas nonhemagglutinating bacteria did not bind. Binding was decreased by an antiserum to the 160-kDa protein and by a preparation of sheep erythrocyte membranes. Fibronectin had no effect. We therefore conclude that binding of S. saprophyticus to uroepithelial cells is mediated by the hemagglutinating activity of the 160-kDa surface protein.
Control of biofilm formation by poly-ethylene-co-vinyl acetate films incorporating nisin.
2010
The aim of this study was to evaluate the effect of poly-ethylene-co-vinyl acetate (EVA) films incorporating different concentrations (0.1%, 0.5% and 1%) of nisin on the biofilm-forming ability of Listeria monocytogenes ATCC 7644, Staphylococcus aureus 815 and Staphylococ-cus epidermidis ATCC 35984. Nisin was incorporated into two grades of EVA (EVA14 and EVA28) in the melt during a common film-blowing operation. The efficacy of EVA/nisin films was evaluated by biofilm biomass measurements and Live/Dead staining in combination with fluorescence microscopy. In order to evaluate whether the nisin incorporation could modify the film surface properties, contact angle measurements and scanning e…
Antibacterial Activity of Flavonoids Against Methicillin-resistant Staphylococcus aureus strains
2000
An experimental and theoretical study was performed on the anti-staphylococcal activity of 18 natural and synthetic flavonoids against methicillin-resistant Staphylococcus aureus strains. The analysed flavonoids belong to three well-differentiated structural patterns: chalcones, flavanones and flavones. The quantitative analysis of the anti-staphylococcal activity of the compounds was carried out by determining their percent inhibition degree. The hierarchical cluster analysis method was used to analyse the anti-MRSA activity of the compounds. With this methodology, the flavonoids were classified into four groups according to their anti-staphylococcal activity (high, sufficient, intermediat…
The role of environmental factors and medium composition on bacteriocin-like inhibitory substances (BLIS) production by Enterococcus mundtii strains
2008
Bacteriocin-like inhibitory substances (BLIS)-producers Enterococcus mundtii WGWT1-1A, WGW11.2, WGJ20.1, WGJ40.2 and WGK53 from raw material origin were subjected to a study for the characterization of antimicrobial compound production under several growth conditions, including different cultivation media, growth temperatures, pHs, different concentrations and sources of nitrogen compounds, carbohydrates and other nutritional factors, and in the presence of different percentages of ethanol and NaCl. The five E. mundtii strains showed different behaviors. However, in all cases, MRS and sour dough bacteria (SDB) were found as the optimal media for BLIS production. In general, the higher BLIS …
Streptococcus Mutans sortāzes A ekspresija, attīrīšana un raksturošana zāļu vielu skrīningam
2019
Slimības, ko izraisa patogēni, īpaši multirezistenti, piemēram, Streptococcus mutans, ir nepieciešams apkarot. Multirezistentu grampozitīvu patogēnu baktēriju transpeptidāzes - sortāzes A - mērķproteīna inhibēšana mazina patogēnu saistīšanās spēju - virulenci - un līdz ar to arī rezistenci. Bakalaura darbā Streptococcus mutans sortāze A tiek izmantota kā instruments, lai pārbaudītu novatoriskus ķīmiskus savienojumus, kam piemīt spēja inhibēt sortāzi A. Mērķis bija, izmantojot zāļu vielu skrīninga metodi, atlasīt ķīmiskas vielas, kam piemīt sortāzes A inhibēšana un kuras varētu izmantot, lai apkarotu multirezistentu grampozitīvu patogēnu izraistītas slimības. Streptococcus mutans sortāzes A …
No klīniskajiem paraugiem izdalīto Streptococcus pneumoniae virulences faktori un rezistence pret antibakteriālajiem līdzekļiem
2020
Ievads: Latvijā un Pasaulē aktuāla problēma ir Streptococcus pneumoniae baktērijas rezistence, kas izveidojusies pret antibakteriālajiem līdzekļiem. Rezistento Streptococcus pneumoniae celmu skaits palielinās ar katru gadu. Preventīvie pasākumi, kas samazinātu rezistences incidenci ir svarīga atbildīga un piesardzīga antibakteriālo līdzekļu izmantošana cilvēku veselības uzlabošanai un pacientu informētība, izpratne par Streptococcus pneumoniae rezistenci. Darba mērķi: Noteikt Streptecoccus pneumoniae jutību pret antibakteriālajiem līdzekļiem, kas iegūti no klīniskā materiāla paraugiem. Materiāli un metodes: Pētījums veikts RAKUS stacionārs ‘’Tuberkulozes un plaušu slimību centrs’’ klīnikas …
No klīniskā materiāla izdalīto Streptococcus pneumoniae jutība pret antibakteriālajiem līdzekļiem
2016
Nozīmīga sabiedrības veselības problēma ir baktēriju rezistence pret antibakteriālajiem līdzekļiem. Pasaulē parādās arvien jauni pret antibakteriālajiem līdzekļiem rezistenti S. pneumoniae celmi. Tas galvenokārt, saistīts ar antibakteriālo līdzekļu nepareizu pielietošanu un plaša spektra preparātu lietošanu, kad ir iespējams izmantot šaura spektra antibakteriālus līdzekļus. Darba mērķis: Noteikt S. pneumoniae jutību pret antibakteriālajiem līdzekļiem, celmiem, kas izdalīti no klīniskā materiāla. Darba uzdevumi: Veikt laboratorijā identificēto S. pneumoniae jutības testus pret antibakteriālajiem līdzekļiem, pielietojot BBLTM DDT un BBLTM E – testu, analizēt statistiskos datus, izmantojot Mic…
Molecular Co-operation between Protein PAM and Streptokinase for Plasmin Acquisition by Streptococcus pyogenes
1998
Bacterial surface-associated plasmin formation is believed to contribute to invasion, although the underlying molecular mechanisms are poorly understood. To define the components necessary for plasmin generation on group A streptococci we used strain AP53 which exposes an M-like protein ("PAM") that contains a plasminogen-binding sequence with two 13-amino acid residues long tandem repeats (a1 and a2). Utilizing an Escherichia coli-streptococcal shuttle vector, we replaced a 29-residue long sequence segment of Arp4, an M-like protein that does not bind plasminogen, with a single (a1) or the combined a1a2 repeats of PAM. When expressed in E. coli, the purified chimeric Arp/PAM proteins both …
Mutations affecting MHC class II binding of the superantigen streptococcal erythrogenic toxin A.
1993
Streptococcal pyrogenic exotoxin A (SPEA) is an important pathogenicity factor of group A streptococci. It is a member of the family of 'superantigens' produced by Staphylococcus aureus and Streptococcus pyogenes, and its T lymphocyte stimulating activity is involved in the pathogenesis of certain diseases caused by pyogenic streptococci. In this study we have generated nine mutant SPEA molecules by substituting amino acids in the regions of homology between different streptococcal and staphylococcal superantigens. An additional mutant was created by deletion of the 10 N-terminal amino acids. The mutants were expressed as fusion proteins. Several mutations led to a loss of function due to a…
Animal rennets as sources of dairy lactic acid bacteria
2014
ABSTRACT The microbial composition of artisan and industrial animal rennet pastes was studied by using both culture-dependent and -independent approaches. Pyrosequencing targeting the 16S rRNA gene allowed to identify 361 operational taxonomic units (OTUs) to the genus/species level. Among lactic acid bacteria (LAB), Streptococcus thermophilus and some lactobacilli, mainly Lactobacillus crispatus and Lactobacillus reuteri , were the most abundant species, with differences among the samples. Twelve groups of microorganisms were targeted by viable plate counts revealing a dominance of mesophilic cocci. All rennets were able to acidify ultrahigh-temperature-processed (UHT) milk as shown by pH …