Coagulase Gene Polymorphism Research Articles

Characterization of Staphylococcus aureus isolated from milk samples for their virulence, biofilm, and antimicrobial resistance

The Staphylococcus aureus (S. aureus) one of the important food borne pathogen from milk, which was investigated in this study. The isolates were screened for antimicrobial resistance, enterotoxin genes, biofilm formation, spa typing, coagulase gene polymorphism and accessory gene regulator types. The prevalence of S. aureus in milk samples was 34.4% (89/259). Methicillin resistant S. aureus (MRSA) was found at 27% (24/89) of the isolates, were classified as community acquired based on SCCmec typing. The 24.71% (22/89) isolates demonstrated multiple antimicrobial resistance (MAR) pattern. However, none of the isolates carried vancomycin and mupirocin resistance genes. The isolates were positive for sea and sed enterotoxin genes and exhibited high frequency of biofilm formation. The High-Resolution Melting and conventional spa typing revealed that the isolates had both animal and community-associated S. aureus clustered origins. Coagulase gene polymorphism and agr typing demonstrated variable genotypic patterns. The finding of this study establishes the prevalence of community associated, enterotoxigenic, biofilm forming and antimicrobial resistance among S. aureus from milk in Chennai city. This emphasizing a potential threat to public health which needs a continuous monitoring system and strategies to mitigate their spread across the food chain and achieve food safety.

Emerging Challenges in Staphylococcus aureus Bloodstream Infections: Insights from Coagulase Typing, Toxin Genes, and Antibiotic Resistance Patterns.

The incidence of complications and mortality associated with Staphylococcus aureus (S. aureus) bloodstream infections has been increasing significantly, particularly in developing countries where control strategies against this virulent pathogen and its resistance to antibacterial agents are insufficient. The aim of this study was to investigate coagulase typing, the prevalence of toxin genes, and the antibiotic resistance profile of S. aureus isolated from bloodstream infections. Antibiotic susceptibility of the isolates was determined by the disk diffusion method. The prevalence of toxin genes was determined using the polymerase chain reaction (PCR) method. Genetic variability of isolates was determined using multiplex PCR based on coagulase gene polymorphism. Out of 120 strains, 55 (46%) were methicillin-resistant S. aureus (MRSA) and 65 (54%) were methicillin-sensitive S. aureus (MSSA). All isolates were susceptible to linezolid and teicoplanin but showed varying levels of resistance to other antibiotics. The highest resistance was observed for ampicillin (92.5%), gentamicin (69.2%), and amikacin (68.3%). Multidrug resistance was observed in all isolates. PCR analysis revealed a higher prevalence of toxin genes in MRSA (tst: 38%, pvl: 29.1%, eta: 10%, and etb: 4.1%) than that in MSSA. According to the coa typing, the most prevalent types were coa III (29.2%), coa II (26.7%), and coa VI (10%). The presence of genetic variability and widespread multidrug resistance in our hospitals emphasizes the circulation of various coa types. Therefore, it is crucial to implement antimicrobial stewardship and infection control measures to prevent and control the spread of these strains.

Evaluation of aminoglycoside modifying enzymes, SCCmec, coagulase gene and PCR-RFLP coagulase gene typing of Staphylococcus aureus isolates from hospitals in Shiraz, southwest of Iran

Staphylococcus aureus is an important human pathogen that causes various infections. Aminoglycosides are broad-spectrum antibiotics used to treat methicillinresistant S. aureus (MRSA) infections. Typing of S. aureus isolates by coagulase gene typing and PCR-RFLP coa gene is a fast and suitable method for epidemiological studies. Aim of the present study was to evaluate the resistance to aminoglycosides, staphylococcal chromosomal cassette mec (SCCmec) types, coagulation typing and PCR-RFLP coa gene in clinical isolates of S. aureus. 192 S. aureus isolates were collected from Namazi and Shahid Faghihi hospitals. Antibiotic resistance was measured by disk diffusion method and MIC was determined for gentamicin. The presence of genes encoding aminoglycoside modifying enzymes (AME) and mecA gene were assessed by PCR. Also the coagulase typing, PCR-RFLP coa gene, and SCCmec typing were performed. Out of 192 isolated S. aureus isolates, 83 (43.2%) MRSA isolates were identified. In this study, a high resistance to streptomycin and gentamicin (98.7%) were observed. Among the AME genes, the aac (6′)-Ie-aph (2″) gene was the most common. Based on the SCCmec typing, it was determined that the prevalence of SCCmec type III (45.8%) was highest. From the amplification of the coa gene, 5 different types were obtained. Also, in digestion of coa gene products by HaeIII enzyme, 10 different RFLP patterns were observed. According to this study, aminoglycoside resistance is increasing among MRSA isolates. As a result, monitoring and control of aminoglycoside resistance can be effective in the treatment of MRSA isolates. Also, typing of S. aureus isolates based on coagulase gene polymorphism is a suitable method for epidemiological studies.

Molecular characterization of Staphylococcus aureus strains isolated from hospitalized patients based on coagulase gene polymorphism analysis: High frequency of vancomycin-intermediate S. aureus and the emergence of coagulase type II in Iran

Staphylococcus aureus is a leading cause of nosocomial infections and a significant contributor to economic and societal cost. There has been a worldwide increase in infections related to S. aureus especially with those expressing a multi-drug resistance that makes the management of the infections difficult. In the current study, it is aimed to investigate the coa gene polymorphism, prevalence, resistance and virulence pattern in S. aureus strains. A total of Ninety-five clinical S. aureus strains were investigated in the study. Antibiogram analysis was done by disk diffusion test method except for vancomycin and mupirocin (broth microdilution). Methicillin resistance was determined by using the cefoxitin disk diffusion test and subsequently PCR of the mecA gene was done. Inducible resistance to clindamycin was identified by D-test. The genetic background was characterized by coagulase typing. The overall prevalence of methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) was 67.4% and 32.6%, respectively. The multidrug resistance (MDR) rate for MRSA isolates was higher than MSSA (87.5% vs 77.4%). Intermediate resistance to vancomycin in S. aureus (VISA) was detected in 11.6% of strains which all were MRSA and isolated from intensive care unit (ICU). Resistance to mupirocin was confirmed in 30.5% of strains which of these 34.5% and 65.5% exhibited resistance to mupirocin in high and low level respectively. The overall prevalence of cMLSB, iMLSB, and MS phenotype was 45.3%, 23.2%, and 3.1% respectively. Both iMLSB and cMLSB phenotypes predominated in MRSA strains. A total of seven coa type were found in this study. coa type II was the most prevalent type (44.2%). Isolates of coa type II had higher detection of pvl and tst genes than those of other types identified. The MRSA-coa II expressed the greatest MDR while coa IVb and VIII were susceptible to all applied antibiotics. Present data revealed that spreading seven coa types of S. aureus with a high prevalence of VISA strains which is a serious threat in our region. Our study supported careful monitoring of vancomycin treatment to prevent the further spread of VISA and VRSA strains.

The molecular epidemiology of Staphylococcus aureus of bovine mastitis origin

The present study was aimed to understand the molecular epidemiology of Staphylococcus aureus (54 isolates), isolated from 422 milk samples obtained from 108 subclinical mastitis affected cows (CMT positive ≥1+ in at least one quarter). The molecular epidemiology of Staphylococcus aureus was studied using coagulase (coa) gene polymorphism, 16S-23S ribosomal spascer (RS-PCR) polymorphism and Staphylococcal protein A (Spa) typing. Staphylococcus aureus produced 7 coagulase genotypes and 8 RS genotypes respectively. Coagulase genotype GTIII (730 bp) was the most prevalent (35 strains) followed by GTV (900 bp, 7 strains) and GTIV (800 bp, 4 strains), whereas RS genotypes GTA accounted for the highest number of strains (31 strains), followed by GTB (11strains), GTH (4 strains) and GTE (3 strains). Coagulase genotype CTIII (730 bp) showed the highest diversity, as isolates within it produced 5 RS genotypes, the majority of them belonging to the RS genotype GTA (29 out of 31 strains). Forty out of 54 Staphylococcus aureus samples isolated in this study were correctly typed by spa typing, and were assigned to 21 known spa types, and one new novel spa type t18462. The study revealed high diversity within Staphylococcus aureus strains, consisting of 7 coagulase genotypes, 8 RS genotypes and 22 spa types.

Coagulase gene polymorphisms of Staphylococcus aureus isolates from patients at Kosti Teaching Hospital, Sudan.

Background Staphylococcus aureus is a common cause of nosocomial infections. Epidemiological typing of S. aureus enables control of its spread. The objective of this study was to investigate coagulase gene polymorphisms of S. aureus isolated from patients at Kosti Hospital in Sudan.Methods In total, 110 S. aureus isolates were recovered from 110 patients who were enrolled in the study. S. aureus strains were isolated on blood agar and MacConkey agar and then identified by conventional tests. Resistance to methicillin was determined by detection of the mecA gene. Polymorphism in the coagulase gene (coa) was investigated using PCR followed by AluI RFLP analysis.Results Methicillin-resistant S. aureus accounted for 62/110 (56 %) of the isolates. PCR of the coa gene showed two different amplicons, one of 680 bp detected in 83/110 (75.5 %) of the isolates and one of 790 bp detected in 27/110 (24.5 %). When digested with the AluI enzyme, the 790 bp amplicon resulted in three restriction fragments of 500, 210 and 80 bp (coa1). Restriction of the 680 bp amplicon gave two patterns; the first (coa2) was found in 22/110 (20 %) of the isolates and showed four fragments of 210, 210, 180 and 80 bp, and the second (coa3) was found in 61/110 (55.5 %) and revealed three fragments of 390, 210 and 80 bp. Most of the coa3 isolates (75.4%) were methicillin-resistant.Conclusion Three polymorphic genotypes of S. aureus were identified in patients at Kosti Hospital. The coa3 genotype was the predominant one and was mostly detected in methicillin-resistant isolates.

PCR-RFLP by AluI for coa gene of methicillin-resistant Staphylococcus aureus (MRSA) isolated from burn wounds, pneumonia and otitis media

Coagulase is considered as the main determinant to distinguish Staphylococcus aureus. The 3′ end coding region of the coagulase gene (coa) has a series of 81 bp tandem repeats varying in number and sites of restriction enzyme among diverse isolates. The polymorphism of the coagulase gene among 45 MRSA isolated from burn wounds, otitis media and pneumonia in Basra city, Iraq, were investigated using PCR-RFLP analysis for 3′ end region with AluI enzyme revealing unique restriction patterns (18 patterns) not described in any previous studies. Particularly, pattern 1 was predominant. Different RFLP patterns of coa were shared among isolates from the different sampling sites.The present study used the polymorphism of Coagulase gene to identify MRSA subtypes, estimate the efficiency of these methods in distinguishing the variable strains and compare these subtypes with the source of isolates.

Coagulase Gene Polymorphism of Staphylococcus Aureus Isolates Collected From Human Clinical Samples in Southeastern Iran

Background: Staphylococcus aureus is one of the most important pathogens in the development of hospital infections. The production of coagulase is directly related to the pathogenicity of S. aureus. The present study was conducted in order to investigate the polymorphism of the coagulase gene (coa) as a coagulase-encoding gene. Methods: 120 clinical samples were collected from patients admitted to Imam Khomeini and Amiralmomenin hospitals in Zabol, southeastern Iran, during 2014 and screened for the presence of S. aureus. Genetic diversity was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR–RFLP) of coa gene and digested by AluI enzyme. Results: Out of 120 clinical samples, 56 isolates were diagnosed as S. aureus and all of these isolates were positive for the 3′ end of the coa gene by PCR. All isolates produced a single band on coa PCR, with molecular sizes ranging from 600 to 850 bp, with the highest frequency of 700 bp (39%). RFLP analysis of coa gene using AluI revealed P1-P4 band patterns with the highest frequency of P1. Conclusions: The results of this study showed that P1 pattern was the most frequent pattern and lowest frequency was observed in P4 pattern. The results of this study suggest that the RFLP of coa gene can be used as a fairly suitable method for determining the genetic differences between S. aureus isolates.

Coagulase gene polymorphism and antimicrobial susceptibility of Staphylococcus aureus isolated from bovine subclinical mastitis milk in Sidi-Bel-Abbes, Algeria

The study was conducted to identify and characterize Staphylococcus aureus in raw milk derived from subclinical mastitis in Sidi-Bel-Abbes Algeria. In this paper, we explore the possibility of detection of the coagulase gene (coa), which encodes the coagulase enzyme, by PCR analysis in antibiotic-resistant isolates, with the latex agglutination phenotype and free coagulase.Out of 336 samples of raw milk examined with California mastitis test (CMT) posi-tive; a total of 142 samples were bacteriologically positive with 56.34% Staphylococcus isolates, 21 (26.25%) isolates were confirmed as S.aureus. Nineteen (90.48%) isolates of S.aureus showed free coagulase on the tube agglutination test. Two atypical S.aureus strains (9.52%) were defective for the clumping factor and / or protein A , determined with the Staphytect plus test and the tube coagulase test. The isolates of S.aureus were resistant to penicillin and tetracycline with 76.19%. Two isolates (9.52%) of S.aureus re-sistant to meticillin (MRSA) were detected in this study, with a MIC of ≥4 μg / liter and a cefoxitin screen test with a MIC of ≥8 μg / liter, and 13 (61.9%) isolates were with a multiresistance phenotype. The 21 isolates were sub-jected to PCR amplification of the 3' end of the coa gene, 18 (85.71%) were revealed on a 1% agarose gel with a single band between 547 bp and 875 bp. The use of the PCR genotypic test to identify the profile of the coa gene can be used as an appropriate identification criterion for differentiating coagulases from S.aureus and for understanding their epidemiology.

Coagulase gene polymorphism, enterotoxigenecity, biofilm production, and antibiotic resistance in Staphylococcus aureus isolated from bovine raw milk in North West India

BackgroundStaphylococcus aureus is the predominant bacterium responsible for various diseases in animals and humans. Preventive strategies could be better implemented by understanding the prevalence, genetic patterns, and the presence of enterotoxin and biofilm-producing genes along with the antibiotic susceptibility of this organism. This study was conducted in Rajasthan, the northwestern state of India, holding the largest population of cattle that makes it the second largest milk producer in India and no such prior information is available on these aspects.MethodsA total of 368 individual quarter bovine raw milk samples were collected from 13 districts of Rajasthan, and screened for the presence of S. aureus. Microbiological and molecular approaches were followed for bacterial identification. Genetic diversity was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR–RFLP) of coagulase gene (coa), whereas enterotoxin and biofilm-producing genes were studied by PCR analysis. Antibiotic strips were employed to study the antibiotic resistance among strains.ResultsIn all, 73 S. aureus strains were obtained from 368 bovine raw milk samples out of that only 30 showed the presence of coa. Nine types of coa patterns ranging from 730 to 1130 bp were observed among these isolates. PCR–RFLP of coa distinguished the isolates into 15 genotypic patterns, of which patterns I, IV, V, and VI were predominant. Of the isolates, 30% were positive for sec, 10% for sea, and 3.3% for seb; these genes are responsible for enterotoxin production, whereas all isolates were found positive for icaAD and eno. The prevalence rates of other biofilm-producing genes fnbA, clfB, ebpS, sasG, fnbB, sasC, cna, bap, fib and, bbp were 97, 93, 90, 80, 80, 77, 53, 27, 10, and 6.6%, respectively. Twenty-seven (90%) strains were multidrug resistant, of which 15 were methicillin resistant. Maximum sensitivity was reported for kanamycin and it could be considered as a drug of choice for controlling S. aureus mediated cattle infections in the studied regions.ConclusionsOverall, these strains could cause several diseases to humans, insisting the need for developing a stricter hygiene program for improving milking practices and animal health.

Detection of newly defined superantigenic toxin genes and coagulase gene polymorphism in Staphylococcus aureus isolates.

The current study aims to use coagulase (coa) polymorphism gene to identify Staphylococcus aureus isolated from stool samples, evaluate the efficiency of these methods in discriminating variable strains, and compare these subtypes with antibiotypes. A total of 100 specimens were collected from patients in Babylon province, Iraq, between July 2016 and September 2016. Twenty S. aureus strains were isolated and identified using standard laboratory microbiological tests. The bacterial isolates were then examined by coa gene restriction fragment length polymorphism genotyping. Out of 20 isolates, coa gene types were classified, and the amplification products showed multiple size bands (500, 600, 700, 800, and 900-bp bands). Coa gene PCR restriction fragment length polymorphisms exhibited seven patterns that ranged from one to four fragments with AluI digestion. The results have demonstrated that many variants of the coa gene are present. At least one type of S. aureus newly described enterotoxin gene (staphylococcal enterotoxins) was harboring in all 20 (100%) of the isolates. The most frequently encountered gene were sei (100.%), seh (5%), seg (65%). Many S. aureus isolates carry at least one of the enterotoxin genes, and (95%) strains harbored more than one toxin gene coding.

Molecular Divergence of Staphylococcus Aureus Isolated from Pork Byproducts Based on Coagulase Gene Polymorphism and The Presence of Enterotoxigenic genes

Molecular Divergence of Staphylococcus Aureus Isolated from Pork Byproducts Based on Coagulase Gene Polymorphism and The Presence of Enterotoxigenic genes

Coagulase gene polymorphism of Staphylococcus aureus in fish and its multiple drug resistant pattern

Coagulase gene polymorphism of Staphylococcus aureus in fish and its multiple drug resistant pattern

Coagulase Gene Polymorphism in Staphylococcus aureus isolated From Chicken and Pork Marketed in Retail Outlets of Chennai

Coagulase Gene Polymorphism in Staphylococcus aureus isolated From Chicken and Pork Marketed in Retail Outlets of Chennai

Antimicrobial Susceptibility Profiles and Coagulase Gene Polymorphism of Staphylococcus aureus Isolated from Bovine Subclinical Mastitis

Antimicrobial Susceptibility Profiles and Coagulase Gene Polymorphism of Staphylococcus aureus Isolated from Bovine Subclinical Mastitis

Coagulase gene polymorphism of Staphylococcus aureus isolates: A study on dairy food products and other foods in Tehran, Iran

Coagulase is considered as a major determinant factor for the identification of Staphylococcus aureus strains. The 3′-end coding region of the coagulase (coa) gene contains a series of 81-bp tandem repeats, which differ in the number and location of enzymatic restriction sites among different isolates. coa PCR-RFLP has been used widely to type S. aureus isolates in epidemiological studies. The current study was conducted to investigate the coagulase gene polymorphisms in S. aureus isolated from various food samples using an in house PCR-RFLP method. A total of 100 strains of S. aureus were isolated from food samples. Isolates were typed by PCR-RFLP analysis using NdeI restriction digestion of the coagulase gene PCR products. Results showed that amplification of coagulase genes from S. aureus produced different PCR products. The isolates were grouped into 18 genotypes using RFLP analysis results of the genes. In this study, the S. aureus isolates have been shown to include more than one coagulase genotype, but only had a few coa genotypes predominated.

PCR and PCR-RFLP genotyping of Staphylococcus aureus coagulase gene: convenience compared to pulse-field gel electrophoresis

Staphylococcus aureus belongs to the group of major contagious mastitis pathogens. We aimed to evaluate the usefulness and the convenience of the coagulase (coa) gene polymorphism to type S. aureus from bovine mastitis milk samples. A total of 22 S. aureus strains were collected from bovine cases of mastitis in four veterinary practices in the Rhone-Alpes region of France and were assessed using coagulase gene’s polymerase chain reaction (PCR) followed by AluI PCR-restriction fragment length polymorphism (PCR-RFLP). Coa gene PCR produced six profiles. The AluI PCR-RFLP displayed nine profiles, giving ten combined patterns. Two genotypes accounted for 50 % of the isolates. Although the results showed that cows from the studied regions were infected by S. aureus strains harboring more than one coagulase genotype, only one or two types predominated. Identification based on PCR-RFLP of the coa gene gave the same results than pulse-field gel electrophoresis (PFGE). Identification based on PCR-RFLP of the coa gene has been considered a more simple and accurate typing method for epidemiological investigations of bovine mastitis.

Molecular typing of staphylococcus aureus strains from Iranian raw milk and dairy products by coagulase gene polymorphisms

Staphylococcus aureus (S. aureus) is one of the most important pathogen in food poisoning and causes gastroenteritis in humans. This study was carried out to determine coagulase gene (coa gene) polymorphisms among S. aureus strains in raw milk and dairy products. A total of 320 samples of raw milk from cow, sheep and goat and 350 samples of traditional dairy products were investigated for S. aureus contamination and their genotypes of coa gene. Among the 320 raw milk samples, S. aureus were detected in 88 (27.5%) samples, and in the 350 dairy products, 87 samples (24.8%) were positive for S. aureus. S. aureus strains isolated from dairy products belong to genotype I and VIII, 45.9% and 18.3% respectively. Among S. aureus strains from raw milk samples, coa gene polymorphisms were observed only in cow milk samples and genotype I and VIII

The Frequency of Methicillin-Resistant Staphylococcus aureus and Coagulase Gene Polymorphism in Egypt.

The current study aimed to use Coagulase gene polymorphism to identify methicillin-resistant Staphylococcus aureus (MRSA) subtypes isolated from nasal carriers in Minia governorate, Egypt, evaluate the efficiency of these methods in discriminating variable strains, and compare these subtypes with antibiotypes. A total of 400 specimens were collected from nasal carriers in Minia governorate, Egypt, between March 2012 and April 2013. Fifty-eight strains (14.5%) were isolated and identified by standard microbiological methods as MRSA. The identified isolates were tested by Coagulase gene RFLP typing. Out of 58 MRSA isolates 15 coa types were classified, and the amplification products showed multiple bands (1, 2, 3, 4, 5, and 8 bands). Coagulase gene PCR-RFLPs exhibited 10 patterns that ranged from 1 to 8 fragments with AluI digestion. Antimicrobial susceptibility testing with a panel of 8 antimicrobial agents showed 6 different antibiotypes. Antibiotype 1 was the most common phenotype with 82.7%. The results have demonstrated that many new variants of the coa gene are present in Minia, Egypt, different from those reported in the previous studies. So surveillance of MRSA should be continued.

Molecular Typing of Methicillin Resistant Staphylococcus aureus Clinical Isolates on the Basis of Protein A and Coagulase Gene Polymorphisms.

Increased frequency of methicillin-resistant Staphylococcus aureus (MRSA) in hospitalized patients requires rapid and reliable characterization of isolates for control of MRSA spread in hospitals. This study evaluated polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) as a molecular typing technique for MRSA strains on the basis of protein A (spa) and coagulase (coa) gene polymorphisms to verify their ability in assessing the relatedness of isolates. Seventy-five MRSA isolates, from different ICUs of Alexandria University Main Hospital, were characterized using antibiotyping and PCR-RFLP analysis of coa and spa genes. Thirty-two antibiotypes were identified. coa gene PCR generated 3 types and 10 subtypes of band patterns. HaeIII restriction digestion of amplified coa gene products produced 5 major banding patterns and 12 subtypes. spa gene PCR products generated 4 major and 11 minor types, and their HaeII restriction digestion showed 5 major and 12 minor banding patterns. The combined coa and spa RFLP patterns generated 22 combined R types. Typing using coa PCR and PCR-RFLP had the same discriminatory index (DI) value (0.64), which was comparable to that of both spa PCR and PCR-RFLP techniques (0.68). The combined grouping increased the DI value to 0.836. The current study revealed that testing for multiple gene polymorphisms is more useful for local epidemiologic purposes.