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Microbiological Research 2009The aim of this study is to determine antibiotic resistance patterns and slime production characteristics of coagulase-negative Staphylococci (CoNS) caused nosocomial...
The aim of this study is to determine antibiotic resistance patterns and slime production characteristics of coagulase-negative Staphylococci (CoNS) caused nosocomial bacteremia. A total of 200 CoNS strains were isolated from blood samples of patients with true bacteremia who were hospitalized in intensive care units and in other departments of Istanbul University Cerrahpasa Medical Hospital between 1999 and 2006. Among 200 CoNS isolates, Staphylococcus epidermidis was the most prevalent species (87) followed by Staphylococcus haemolyticus (23), Staphylococcus hominis (19), Staphylococcus lugdunensis (18), Staphylococcus capitis (15), Staphylococcus xylosus (10), Staphylococcus warneri (8), Staphylococcus saprophyticus (5), Staphylococcus lentus (5), Staphylococcus simulans (4), Staphylococcus chromogenes (3), Staphylococcus cohnii (1), Staphylococcus schleiferi (1), and Staphylococcus auricularis (1). Resistance to methicillin was detected in 67.5% of CoNS isolates. Methicillin-resistant CoNS strains were determined to be more resistant to antibiotics than methicillin-susceptible CoNS strains. Resistance rates of methicillin-resistant and methicillin-susceptible CoNS strains to the antibacterial agents, respectively, were as follows: gentamicin 90% and 17%, erythromycin 80% and 37%, clindamycin 72% and 18%, trimethoprim-sulfamethoxazole 68% and 38%, ciprofloxacin 67% and 23%, tetracycline 60% and 45%, chloramphenicol 56% and 13% and fusidic acid 25% and 15%. None of the strains were resistant to vancomycin and teicoplanin. Slime production was detected in 86 of 200 CoNS strains. Resistance to methicillin was found in 81% of slime-positive and in 57% of slime-negative strains. Our results indicated that there is a high level of resistance to widely used agents in causative methicillin-resistant CoNS strains. However fusidic acid has the smallest resistance ratio, with the exception of glycopeptides. Additionally, most S. epidermidis strains were slime-positive, with statistically significant (p<0.001) association between methicillin resistance and slime production.
Topics: Bacteremia; Coagulase; Cross Infection; Drug Resistance, Bacterial; Hospital Units; Humans; Staphylococcal Infections; Staphylococcus; Turkey
PubMed: 17475456
DOI: 10.1016/j.micres.2007.03.004 -
BMC Veterinary Research Nov 2013Coagulase-negative staphylococci (CNS) cause usually subclinical or mild clinical bovine mastitis, which often remains persistent. Symptoms are usually mild, mostly only...
BACKGROUND
Coagulase-negative staphylococci (CNS) cause usually subclinical or mild clinical bovine mastitis, which often remains persistent. Symptoms are usually mild, mostly only comprising slight changes in the appearance of milk and possibly slight swelling. However, clinical mastitis with severe signs has also been reported. The reasons for the differences in clinical expression are largely unknown. Macrophages play an important role in the innate immunity of the udder. This study examined phagocytosis and killing by mouse macrophage cells of three CNS species: Staphylococcus chromogenes (15 isolates), Staphylococcus agnetis (6 isolates) and Staphylococcus simulans (15 isolates). Staphylococcus aureus (7 isolates) was also included as a control.
RESULTS
All the studied CNS species were phagocytosed by macrophages, but S. simulans resisted phagocytosis more effectively than the other CNS species. Only S. chromogenes was substantially killed by macrophages. Significant variations between isolates were seen in both phagocytosis and killing by macrophages and were more common in the killing assays. Significant differences between single CNS species and S. aureus were observed in both assays.
CONCLUSION
This study demonstrated that differences in the phagocytosis and killing of mastitis-causing staphylococci by macrophages exist at both the species and isolate level.
Topics: Animals; Cattle; Feeder Cells; Female; Macrophages; Mastitis, Bovine; Mice; Mice, Inbred BALB C; Phagocytosis; Staphylococcal Infections; Staphylococcus
PubMed: 24207012
DOI: 10.1186/1746-6148-9-227 -
Iranian Journal of Microbiology Apr 2023secretes an antimicrobial compound called lysostaphin, which has bactericidal properties. It destroys staphylococci through the hydrolysis of peptidoglycan in the cell...
BACKGROUND AND OBJECTIVES
secretes an antimicrobial compound called lysostaphin, which has bactericidal properties. It destroys staphylococci through the hydrolysis of peptidoglycan in the cell wall. Therefore, this unique property indicates the high ability of lysostaphin in the treatment of staphylococcal infections and is considered as an anti-staphylococcal agent.
MATERIALS AND METHODS
BL21 (DE3) competent cells were transformed with pET32a-lysostaphin clone and induced by isopropyl-β-D-thio-galactoside (IPTG). The recombinant protein was purified by affinity chromatography. Recombinant lysostaphin -A-based ointment was used for external wound healing in animal model. activity of ointment was evaluated by clinical evidences and cytological microscopic assessment.
RESULTS
Our results showed the recombinant protein was produced exactly. The results of checkerboard tests showed MIC, MBC and antibacterial activity test an acute reduction of cell viability during the use of lysostaphin, and SEM results approved the intense wrecking effects of lysostaphin in combination on bacterial cells. Macroscopic findings and microscopic data showed that the recombinant lysostaphin ointment was effective on excisional wound healing.
CONCLUSION
Our findings proved that the recombinant lysostaphin ointment was effective on wound healing due to infection.
PubMed: 37193239
DOI: 10.18502/ijm.v15i2.12476 -
Medical Microbiology and Immunology 1988The polyvalent staphylococcal bacteriophage U16 failed to adsorb to an encapsulated Staphylococcus simulans strain. Partially purified cell wall and teichoic acid of...
The polyvalent staphylococcal bacteriophage U16 failed to adsorb to an encapsulated Staphylococcus simulans strain. Partially purified cell wall and teichoic acid of this strain could, however, inactivate bacteriophage U16 to a great extent, indicating the presence of the phage receptor. It is concluded that the capsule of Staphylococcus simulans acts as a barrier for the interaction of the phage with its receptor in the bacterial cell wall.
Topics: Abscess; Absorption; Cell Wall; Humans; Kinetics; Receptors, Virus; Staphylococcus; Staphylococcus Phages
PubMed: 2971134
DOI: 10.1007/BF00211222 -
Antimicrobial susceptibility of coagulase-negative Staphylococcus species isolated from bovine milk.Veterinary Microbiology Feb 2009Coagulase-negative Staphylococcus (CNS) isolates (n=168) obtained from milk from heifers and dairy cows were screened for minimum inhibitory concentration (MIC) to...
Coagulase-negative Staphylococcus (CNS) isolates (n=168) obtained from milk from heifers and dairy cows were screened for minimum inhibitory concentration (MIC) to antimicrobials used commonly for mastitis therapy. Of the 10 CNS species included in the study, the predominant species were Staphylococcus chromogenes (n=61), Staphylococcus epidermidis (n=37), Staphylococcus hyicus (n=37), and Staphylococcus simulans (n=16). The majority of CNS was susceptible to ampicillin, oxacillin, cephalothin, and ceftiofur. Erythromycin and pirlimycin were also very effective in vitro inhibitors of CNS. The only exception was observed with S. epidermidis. Of 37 S. epidermidis evaluated, 13 (35%) exhibited efflux-based resistance to erythromycin (> or =16 microg/ml) encoded by msrA and one isolate carried ermC encoding ribosomal methylase-based resistance to both erythromycin (> or =64 microg/ml) and pirlimycin (> or =64 microg/ml). A total of 17 S. epidermidis, 11 S. chromogenes, and one S. hyicus exhibited phenotypic resistance to ampicillin (> or =0.5 microg/ml). Constitutive beta-lactamase production was observed in all ampicillin resistant isolates except 4 S. epidermidis that exhibited inducible beta-lactamase production. Induced beta-lactamase production was also observed in 13 S. epidermidis that were phenotypically susceptible to the entire MIC panel. All isolates that produced beta-lactamase either constitutively or by induction carried blaZ. S. epidermidis (n=12, 32%) that were resistant to methicillin (oxacillin > or =0.5 microg/ml) carried low affinity penicillin-binding protein encoded by mecA. Most multi-drug resistant (MDR) S. epidermidis (> or =2 resistance genes) were resistant to ampicillin, erythromycin and methicillin. All except one MDR S. epidermidis had icaAB, which encodes for polysaccharide intercellular adhesion. Based on pulsed field gel electrophoresis, MDR S. epidermidis were closely related genotypically, and were isolated from different cows on the same farm suggesting clonal dissemination. Bovine S. epidermidis share antimicrobial resistance patterns and virulence determinants of strains observed in human infections. Studying CNS at the species level can provide valuable information about species-specific differences that can be vital data for effective mastitis therapy and management.
Topics: Animals; Anti-Bacterial Agents; Cattle; Drug Resistance, Bacterial; Genetic Variation; Genotype; Mastitis, Bovine; Microbial Sensitivity Tests; Milk; Phylogeny; Staphylococcal Infections; Staphylococcus
PubMed: 18950969
DOI: 10.1016/j.vetmic.2008.09.006 -
The Journal of Infection Mar 1991
Topics: Aged; Aged, 80 and over; Aortic Valve; Endocarditis, Bacterial; Floxacillin; Heart Valve Diseases; Humans; Male
PubMed: 2026900
DOI: 10.1016/0163-4453(91)91899-9 -
AIMS Microbiology 2019The increasing spread of antibiotic-resistant microorganisms has led to the necessity of developing alternative antimicrobial treatments. The use of peptidoglycan...
The increasing spread of antibiotic-resistant microorganisms has led to the necessity of developing alternative antimicrobial treatments. The use of peptidoglycan hydrolases is a promising approach to combat bacterial infections. In our study, we constructed a 2 kb-triple-acting fusion gene () encoding the N-terminal amidase-5 domain of streptococcal LambdaSA2 prophage endolysin (D-glutamine-L-lysin endopeptidase), a mid-protein amidase-2 domain derived from the staphylococcal phage 2638A endolysin (N-acetylmuramoyl-L-alanine amidase) and the mature version (246 residues) of the Lysostaphin bacteriocin (glycyl-glycine endopeptidase) at the C-terminus. The gene was expressed in plants using the non-replicating (CPMV)-based vector pEAQ-HT and the replicating AltMV)-based pGD5TGB123-MCS-CP3 vector, and in using pET expression vectors pET26b+ and pET28a+. The resulting poor expression of this fusion protein in plants prompted the construction of a gene codon-optimized for expression in tobacco plants, resulting in an improved codon adaptation index (CAI) from 0.79 ( gene) to 0.93 ( gene). Incorporation of the nt gene into the pEAQ-HT vector, followed by transient expression in , led to accumulation of TFnt to an approximate level of 0.12 mg/g of fresh leaf weight. Antimicrobial activity of purified plant- and bacterial-produced TFnt proteins was assessed against two strains of Gram-positive 305 and Newman. The results showed that plant-produced TFnt protein was preferentially active against 305, showing 14% of growth inhibition, while the bacterial-produced TFnt revealed significant antimicrobial activity against both strains, showing 68 (IC 25 µg/ml) and 60% (IC 71 µg/ml) growth inhibition against 305 and Newman, respectively. Although the combination of codon optimization and transient expression using the non-replicating pEAQ-HT expression vector facilitated production of the TFnt protein in plants, the most functionally active antimicrobial protein was obtained using the prokaryotic expression system.
PubMed: 31384710
DOI: 10.3934/microbiol.2019.2.158 -
Plasmid Nov 2009Staphylococcus simulans biovar staphylolyticus, the lysostaphin-producing organism, contains five plasmids designated pACK1-pACK5. pACK4 was found to be relaxable and to...
Staphylococcus simulans biovar staphylolyticus, the lysostaphin-producing organism, contains five plasmids designated pACK1-pACK5. pACK4 was found to be relaxable and to share sequence similarity with a number of well-characterized mobilizable plasmids from other staphylococci. All mobilizable staphylococcal plasmids characterized to date mediate resistance to various antibiotics, but pACK4 is unique because it contains no recognizable antibiotic resistance genes. pACK4 was found to contain an origin of transfer (oriT) region that shares inverted repeat regions and the same nic site as several other mobilizable staphylococcal plasmids. The presence of this conserved oriT region suggested that pACK4 might be mobilized in the presence of a conjugative plasmid. Filter mating studies revealed that pACK4 was mobilized by the conjugative plasmid pGO1. In addition, pACK4 was found to be virtually identical to the recently described plasmid pVGA from Staphylococcus aureus, except that pVGA contains an additional region (vgaA) that confers resistance to pleuromutilin, streptogramin A, and lincosamide. The high sequence similarity among pACK4, pVGA, and several previously described mobilizable staphylococcal plasmids suggests a common origin for these plasmids.
Topics: Anti-Bacterial Agents; Base Sequence; Conjugation, Genetic; Diterpenes; Drug Resistance, Bacterial; Lincosamides; Molecular Sequence Data; Plasmids; Polycyclic Compounds; Staphylococcus; Streptogramin A; Pleuromutilins
PubMed: 19715721
DOI: 10.1016/j.plasmid.2009.08.003 -
Clinical Microbiology and Infection :... Mar 2005As routine identification of coagulase-negative staphylococci is problematic, the performance of automated ribotyping was evaluated for identification of...
As routine identification of coagulase-negative staphylococci is problematic, the performance of automated ribotyping was evaluated for identification of coagulase-negative staphylococci other than Staphylococcus epidermidis. In total, 177 isolates were tested, comprising 149 isolates from blood samples, 15 isolates that were not identified by internal transcribed spacer (ITS)-PCR in a previous study, and 13 reference strains. The identification results were compared with those obtained by the API 20 Staph system, with standard phenotypic and molecular methods as reference. Most (n = 166; 93.8%) isolates were identified correctly by automated ribotyping. For 61 isolates, API 20 Staph and ribotyping were in agreement, but for 105 isolates, ribotyping provided correct identification and API 20 Staph did not. Four isolates not identified by automated ribotyping were recognised correctly by API 20 Staph. The remaining seven isolates could not be identified by either of the two methods. Automated ribotyping was able to distinguish Staphylococcus capitis reliably from Staphylococcus caprae. The results demonstrate the value of automated ribotyping for identification of coagulase-negative Staphylococcus (CoNS) isolates from human sources and may help to clarify the clinical relevance of CoNS species. In addition, automated ribotyping was able to detect polymorphisms that may be useful for epidemiological purposes within S. capitis, Staphylococcus hominis, Staphylococcus haemolyticus, Staphylococcus simulans, S. caprae, Staphylococcus warneri, Staphylococcus lugdunensis, Staphylococcus schleiferi, Staphylococcus sciuri, Staphylococcus pasteuri and Staphylococcus xylosus.
Topics: Phenotype; RNA, Bacterial; RNA, Ribosomal, 16S; Ribotyping; Species Specificity; Staphylococcus
PubMed: 15715714
DOI: 10.1111/j.1469-0691.2004.01052.x -
Biochemical and Biophysical Research... May 1989Staphylococcus simulans biovar staphylolyticus, the lysostaphin-producing organism, secretes a staphylolytic endopeptidase (EC 3.4.99.17) that is encoded on plasmid...
Staphylococcus simulans biovar staphylolyticus, the lysostaphin-producing organism, secretes a staphylolytic endopeptidase (EC 3.4.99.17) that is encoded on plasmid pACK1. Susceptibility of pACK1-cured strains to lysis by endopeptidase established that resistance to this enzyme is not an inherent property of the organism but rather is encoded on this dispensable plasmid. Furthermore, the enzyme is not an autolysin that is essential for cell wall synthesis because strains lacking the endopeptidase gene grew normally.
Topics: Lysostaphin; Mutation; Plasmids; Staphylococcus
PubMed: 2730641
DOI: 10.1016/s0006-291x(89)80117-2