scholarly journals Identification of hemolysin encoding genes and their association with antimicrobial resistance pattern among clinical isolates of coagulase-negative Staphylococci

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Mona Nasaj ◽  
Zahra Saeidi ◽  
Babak Asghari ◽  
Ghodratollah Roshanaei ◽  
Mohammad Reza Arabestani
2019 ◽  
Author(s):  
Mona Nasaj ◽  
Zahra Saeidi ◽  
Babak Asghari ◽  
Ghodratollah Roshanaei ◽  
Mohammad Arabestani

Abstract Objection : Coagulase-negative staphylococci (CoNS) are considered opportunistic pathogens which capable of producing several toxins, enzymes and also resistance genes. The current study aimed to determine the occurrence of different hemolysins and patterns of antibiotic resistance among CoNS species. Results : The highest frequency of antibiotic resistance was observed against cefoxitin in 49 isolates (53.8%), and the lowest resistance was against novobiocin in 5 isolates (5.5%). None of the isolates were resistant to vancomycin. The prevalence of hla, hla_yidD, hld, and hlb genes were determined as 87.9%, 62.6%, 56%, and 47.3%, respectively. The hla/yidD and hld genes were detected in 69.4% of S. epidermidis and the hla gene in 94.6% of S. haemolyticus ; hlb gene was detected in 53.1% of the S. epidermidis isolates. mecA gene was identified in 50 (55%) of the CoNS isolates. In conclusion, the results of statistical analysis showed that the hld gene had a significant association with resistance to levofloxacin and erythromycin and the hlb with clindamycin resistance. The results of this study showed that there is a significant relationship between hemolysin encoding genes and antibiotic resistance patterns; therefore, detection of virulence factors associated with antibiotic resistance has become a significant issue of concern.


2013 ◽  
Vol 10 (12) ◽  
pp. 1044-1049 ◽  
Author(s):  
Jacqueline Ellen Camelo Batista ◽  
Ewerton Lucena Ferreira ◽  
Danielle Cristina de Oliveira Nascimento ◽  
Roberta Ferreira Ventura ◽  
Wagner Luis Mendes de Oliveira ◽  
...  

Pathogens ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 420 ◽  
Author(s):  
Mst. Sonia Parvin ◽  
Sudipta Talukder ◽  
Md. Yamin Ali ◽  
Emdadul Haque Chowdhury ◽  
Md. Tanvir Rahman ◽  
...  

Escherichia coli is known as one of the most important foodborne pathogens in humans, and contaminated chicken meat is an important source of foodborne infection with this bacterium. The occurrence of extended-spectrum β-lactamase (ESBL)-producing E. coli (ESBL-Ec), in particular, in chicken meat is considered a global health problem. This study aimed to determine the magnitude of E. coli, with special emphasis on ESBL-Ec, along with their phenotypic antimicrobial resistance pattern in frozen chicken meat. The study also focused on the determination of ESBL-encoding genes in E. coli. A total of 113 frozen chicken meat samples were purchased from 40 outlets of nine branded supershops in five megacities in Bangladesh. Isolation and identification of E. coli were done based on cultural and biochemical properties, as well as PCR assay. The resistance pattern was determined by the disc diffusion method. ESBL-encoding genes were determined by multiplex PCR. The results showed that 76.1% of samples were positive for E. coli, of which 86% were ESBL producers. All the isolates were multidrug-resistant (MDR). Resistance to 9–11 and 12–13 antimicrobial classes was observed in 38.4% and 17.4% isolates, respectively, while only 11.6% were resistant to 3–5 classes. Possible extensive drug resistance (pXDR) was found in 2.3% of isolates. High single resistance was observed for oxytetracycline (93%) and amoxicillin (91.9%), followed by ampicillin (89.5%), trimethoprim–sulfamethoxazole, and pefloxacin (88.4%), and tetracycline (84.9%). Most importantly, 89.6% of isolates were resistant to carbapenems. All the isolates were positive for the blaTEM gene. However, the blaSHV and blaCTX-M-2 genes were identified in two ESBL-non producer isolates. None of the isolates carried the blaCTX-M-1 gene. This study provided evidence of the existence of MDR and pXDR ESBL-Ec in frozen chicken meat in Bangladesh, which may pose a risk to human health if the meat is not properly cooked or pickled raw only. This emphasizes the importance of the implementation of good slaughtering and processing practices by the processors.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Leila Ahmadian ◽  
Zahra Norouzi Bazgir ◽  
Mohammad Ahanjan ◽  
Reza Valadan ◽  
Hamid Reza Goli

In recent years, the prevalence of resistance to aminoglycosides among clinical isolates of Pseudomonas aeruginosa is increasing. The aim of this study was to investigate the role of aminoglycoside-modifying enzymes (AMEs) in resistance to aminoglycosides in clinical isolates of P. aeruginosa. The clinical isolates were collected from different hospitals. Disk agar diffusion test was used to determine the antimicrobial resistance pattern of the clinical isolates, and the minimum inhibitory concentration of aminoglycosides was detected by microbroth dilution method. The PCR was performed for discovery of aminoglycoside-modifying enzyme-encoding genes. Among 100 screened isolates, 43 (43%) isolates were resistant to at least one tested aminoglycosides. However, 13 (13%) isolates were resistant to all tested aminoglycosides and 37 isolates were detected as multidrug resistant (MDR). The resistance rates of P. aeruginosa isolates against tested antibiotics were as follows: ciprofloxacin (41%), piperacillin-tazobactam (12%), cefepime (32%), piperacillin (26%), and imipenem (31%). However, according to the MIC method, 13%, 32%, 33%, and 37% of the isolates were resistant to amikacin, gentamicin, tobramycin, and netilmicin, respectively. The PCR results showed that AAC(6 ′ )-Ib was the most commonly (26/43, 60.4%) identified AME-encoding gene followed by AAC(6 ′ )-IIa (41.86%), APH(3 ′ )-IIb (34.8%), ANT(3 ″ )-Ia (18.6), ANT(2 ″ )-Ia (13.95%), and APH(3 ″ )-Ib (2.32%). However, APH(3 ′ )-Ib was not found in any of the studied isolates. The high prevalence of AME-encoding genes among aminoglycoside-resistant P. aeruginosa isolates in this area indicated the important role of AMEs in resistance to these antibiotics similar to most studies worldwide. Due to the transmission possibility of these genes between the Gram-negative bacteria, we need to control the prescription of aminoglycosides in hospitals.


MethodsX ◽  
2020 ◽  
Vol 7 ◽  
pp. 101031
Author(s):  
Mojtaba Moosavian ◽  
Khadijeh Ahmadi ◽  
Saeed Shoja ◽  
Jalal Mardaneh ◽  
Fatemeh Shahi ◽  
...  

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