scholarly journals Antimicrobial resistance and novel mutations detected in the gyrA and parC genes of Pseudomonas aeruginosa strains isolated from companion dogs

2020 ◽  
Author(s):  
Youjin Park ◽  
Jaeyoung Oh ◽  
Sowon Park ◽  
Samuth Sum ◽  
Wonkeun Song ◽  
...  

Abstract Background: Fluoroquinolone agents, such as enrofloxacin and marbofloxacin, are commonly used for pseudomonal infection in veterinary medicine. However, the rate of resistance to fluoroquinolones is rapidly increasing, according to multiple studies in various countries. Point mutations in the quinolone resistance-determining region (QRDR) are closely related to the increased fluoroquinolone resistance of Pseudomonas aeruginosa. The aim of this study was to investigate current antimicrobial susceptibility and fluoroquinolone resistance in P. aeruginosa strains isolated from dogs. The presence of point mutations in the QRDR was confirmed by gyrA and parC polymerase chain reaction and nucleotide sequencing analysis.Results: A total of 84 nonduplicated P. aeruginosa strains were obtained from 228 healthy dogs (healthy group) and 260 dogs with clinical signs (infected group). Among these isolates, 38 strains from the healthy group were detected in several sample types, whereas 46 strains from the infected group were obtained mostly from dogs’ ears with otitis externa (41/260, 15.8%). All strains were resistant to nalidixic acid, while some were also resistant to enrofloxacin (23/84, 27.4%), marbofloxacin (17/84, 20.2%), levofloxacin (12/84, 14.3%), or ciprofloxacin (11/84, 13.1%). Enrofloxacin resistance was significantly higher in strains from the infected group than in those from the healthy group (p<0.05). Among the 23 fluoroquinolone-resistant strains, 8 and 4 different mutations were detected in the gyrA and parC genes, respectively. Mutations in gyrA were significantly common in the infected group (p<0.05). Hotspots for the gyrA and parC mutations were Thr83 (34.8%, 8/23) and Pro116 (91.3%, 21/23), respectively. Double and triple mutations were also found in 5 of the strains.Conclusion: Novel mutations in the gyrA and parC genes were first found in P. aeruginosa isolated from companion dogs in South Korea. These findings suggest that it is important to encourage prudent use of fluoroquinolone antibiotics in canine pseudomonal infection treatment.

2019 ◽  
Author(s):  
Youjin Park ◽  
Jaeyoung Oh ◽  
Sowon Park ◽  
Samuth Sum ◽  
Wonkeun Song ◽  
...  

Abstract Background Fluoroquinolone agents, such as enrofloxacin and marbofloxacin, are commonly used in pseudomonal infection in veterinary medicine. However, the resistance rate to fluoroquinolone is rapidly increasing according to multiple studies in various countries. The point mutation in quinolone resistance determining region (QRDR) is closely related to increased fluoroquinolone resistance of Pseudomonas aeruginosa . The aim of this study was to investigate current antimicrobial susceptibility and fluoroquinolone resistance in Pseudomonas aeruginosa strains isolated from dogs. The presence of the point mutations in the QRDR was confirmed by gyrA and parC polymerase chain reaction and nucleotide sequencing analysis. Results A total of 84 nonduplicated P. aeruginosa isolates were obtained from 228 healthy dogs (healthy group) and 260 dogs with clinical signs (infected group). From these, 38 isolates from the healthy group were detected in several samples, whereas 46 isolates from the infected group were mostly obtained from dogs’ ears with otitis externa (41/260, 15.8%). All isolates were resistant to nalidixic acid, while some were also resistant to enrofloxacin (23/84, 27.4%), marbofloxacin (17/84, 20.2%), levofloxacin (12/84, 14.3%), or ciprofloxacin (11/84, 13.1%). Enrofloxacin resistance was significantly higher in strains from the infected group than that of the healthy group ( p <0.05). Among the 23 fluoroquinolone-resistant isolates, 8 and 4 different mutations were detected in the gyrA and parC genes, respectively. Mutations in gyrA were significantly common in the infected group ( p <0.05). Hotspots for the gyrA and parC mutations were Thr83 (34.8%, 8/23) and Pro116 (91.3%, 21/23), respectively. Double and triple mutations were also found in 5 of the isolates. Conclusion Novel mutations in the gyrA and parC genes were first found in P. aeruginosa isolates from companion dogs in South Korea. These findings suggest that it is important to know the prudent use of fluoroquinolone antibiotics in canine pseudomonas infection treatment.


2020 ◽  
Author(s):  
Youjin Park ◽  
Jaeyoung Oh ◽  
Sowon Park ◽  
Samuth Sum ◽  
Wonkeun Song ◽  
...  

Abstract Background: Fluoroquinolone agents, such as enrofloxacin and marbofloxacin, are commonly used in for pseudomonal infection in veterinary medicine. However, the rate of resistance rate to fluoroquinolone s is rapidly increasing , according to multiple studies in various countries. The p P oint mutation s in the quinolone resistance - determining region (QRDR) is are closely related to the increased fluoroquinolone resistance of Pseudomonas aeruginosa . The aim of this study was to investigate current antimicrobial susceptibility and fluoroquinolone resistance in P. aeruginosa strains isolated from dogs. The presence of the point mutations in the QRDR was confirmed by gyrA and parC polymerase chain reaction and nucleotide sequencing analysis. Results: A total of 84 nonduplicated P. aeruginosa strains were obtained from 228 healthy dogs (healthy group) and 260 dogs with clinical signs (infected group). From Of Among these isolates , 38 strains from the healthy group were detected in several sample type s, whereas 46 strains from the infected group were mostly obtained mostly from dogs’ ears with otitis externa (41/260, 15.8%). All strains were resistant to nalidixic acid, while some were also resistant to enrofloxacin (23/84, 27.4%), marbofloxacin (17/84, 20.2%), levofloxacin (12/84, 14.3%), or ciprofloxacin (11/84, 13.1%). Enrofloxacin resistance was significantly higher in strains from the infected group than in th ose at of from the healthy group ( p <0.05). Among the 23 fluoroquinolone-resistant strains, 8 and 4 different mutations were detected in the gyrA and parC genes, respectively. Mutations in gyrA were significantly common in the infected group ( p <0.05). Hotspots for the gyrA and parC mutations were Thr83 (34.8%, 8/23) and Pro116 (91.3%, 21/23), respectively. Double and triple mutations were also found in 5 of the strains. Conclusion: Novel mutations in the gyrA and parC genes were first found in P. aeruginosa isolated from companion dogs in South Korea. These findings suggest that it is important to alert encourage the prudent use of fluoroquinolone antibiotics in canine pseudomona l s infection treatment.


2020 ◽  
Author(s):  
Youjin Park ◽  
Jaeyoung Oh ◽  
Sowon Park ◽  
Samuth Sum ◽  
Wonkeun Song ◽  
...  

Abstract Background: Fluoroquinolone agents, such as enrofloxacin and marbofloxacin, are commonly used in for pseudomonal infection in veterinary medicine. However, the rate of resistance rate to fluoroquinolone s is rapidly increasing , according to multiple studies in various countries. The p P oint mutation s in the quinolone resistance - determining region (QRDR) is are closely related to the increased fluoroquinolone resistance of Pseudomonas aeruginosa . The aim of this study was to investigate current antimicrobial susceptibility and fluoroquinolone resistance in P. aeruginosa strains isolated from dogs. The presence of the point mutations in the QRDR was confirmed by gyrA and parC polymerase chain reaction and nucleotide sequencing analysis. Results: A total of 84 nonduplicated P. aeruginosa strains were obtained from 228 healthy dogs (healthy group) and 260 dogs with clinical signs (infected group). From Of Among these isolates , 38 strains from the healthy group were detected in several sample type s, whereas 46 strains from the infected group were mostly obtained mostly from dogs’ ears with otitis externa (41/260, 15.8%). All strains were resistant to nalidixic acid, while some were also resistant to enrofloxacin (23/84, 27.4%), marbofloxacin (17/84, 20.2%), levofloxacin (12/84, 14.3%), or ciprofloxacin (11/84, 13.1%). Enrofloxacin resistance was significantly higher in strains from the infected group than in th ose at of from the healthy group ( p <0.05). Among the 23 fluoroquinolone-resistant strains, 8 and 4 different mutations were detected in the gyrA and parC genes, respectively. Mutations in gyrA were significantly common in the infected group ( p <0.05). Hotspots for the gyrA and parC mutations were Thr83 (34.8%, 8/23) and Pro116 (91.3%, 21/23), respectively. Double and triple mutations were also found in 5 of the strains. Conclusion: Novel mutations in the gyrA and parC genes were first found in P. aeruginosa isolated from companion dogs in South Korea. These findings suggest that it is important to alert encourage the prudent use of fluoroquinolone antibiotics in canine pseudomona l s infection treatment. Keywords: companion dogs, P. aeruginosa , novel mutations, gyrA , parC


2020 ◽  
Author(s):  
Youjin Park ◽  
Jaeyoung Oh ◽  
Sowon Park ◽  
Samuth Sum ◽  
Wonkeun Song ◽  
...  

Abstract Background: Fluoroquinolone agents, such as enrofloxacin and marbofloxacin, are commonly used in for pseudomonal infection in veterinary medicine. However, the rate of resistance rate to fluoroquinolone s is rapidly increasing , according to multiple studies in various countries. The p P oint mutation s in the quinolone resistance - determining region (QRDR) is are closely related to the increased fluoroquinolone resistance of Pseudomonas aeruginosa . The aim of this study was to investigate current antimicrobial susceptibility and fluoroquinolone resistance in P. aeruginosa strains isolated from dogs. The presence of the point mutations in the QRDR was confirmed by gyrA and parC polymerase chain reaction and nucleotide sequencing analysis. Results: A total of 84 nonduplicated P. aeruginosa strains were obtained from 228 healthy dogs (healthy group) and 260 dogs with clinical signs (infected group). From Of Among these isolates , 38 strains from the healthy group were detected in several sample type s, whereas 46 strains from the infected group were mostly obtained mostly from dogs’ ears with otitis externa (41/260, 15.8%). All strains were resistant to nalidixic acid, while some were also resistant to enrofloxacin (23/84, 27.4%), marbofloxacin (17/84, 20.2%), levofloxacin (12/84, 14.3%), or ciprofloxacin (11/84, 13.1%). Enrofloxacin resistance was significantly higher in strains from the infected group than in th ose at of from the healthy group ( p <0.05). Among the 23 fluoroquinolone-resistant strains, 8 and 4 different mutations were detected in the gyrA and parC genes, respectively. Mutations in gyrA were significantly common in the infected group ( p <0.05). Hotspots for the gyrA and parC mutations were Thr83 (34.8%, 8/23) and Pro116 (91.3%, 21/23), respectively. Double and triple mutations were also found in 5 of the strains. Conclusion: Novel mutations in the gyrA and parC genes were first found in P. aeruginosa isolated from companion dogs in South Korea. These findings suggest that it is important to alert encourage the prudent use of fluoroquinolone antibiotics in canine pseudomona l s infection treatment.


2021 ◽  
Author(s):  
Xiangke Duan ◽  
Yanrong Pan ◽  
Zhao Cai ◽  
Yumei Liu ◽  
Yingdan Zhang ◽  
...  

Abstract BackgroundPseudomonas aeruginosa is a notorious opportunistic pathogen causing various biofilm-related infections. Biofilm formation is a unique microbial strategy that allows P. aeruginosa to survive adverse conditions such as antibiotic treatment and human immune responses. ResultsIn this study, we experimentally evolved P. aeruginosa PAO1 biofilms for cyclic treatment in the presence of high dose of imipenem, and enriched hyperbiofilm mutants within six cycles in two independent lineages. The competition assay showed the evolved hyperbiofilm mutants can outcompete the ancestral strain within biofilm by prolonging the biofilm mode of growth but not in planktonic cultures. Whole-genome sequencing analysis revealed the hyperbiofilm phenotype is caused by point mutations in rpoS gene in all independently evolved mutants and the same mutation was found in P. aeruginosa clinical isolates. We further showed that mutation in rpoS enhanced biofilm formation by prolonging the biofilm mode of growth and elevating the intracellular c-di-GMP level. Mutation in rpoS increased pyocyanin production and virulence in both P. aeruginosa laboratory strains and clinical isolates. ConclusionHere, our study revealed that antibiotic treatment of biofilm-related P. aeruginosa infections might induce a hyperbiofilm phenotype via rpoS mutation, which might partially explain antimicrobial treatment failure of many P. aeruginosa biofilm-related infections.


1999 ◽  
Vol 43 (2) ◽  
pp. 406-409 ◽  
Author(s):  
Takashi Takenouchi ◽  
Eiko Sakagawa ◽  
Mie Sugawara

ABSTRACT gyrA point mutations in 335 clinical Pseudomonas aeruginosa isolates were examined mainly by nonisotopic single-strand conformation polymorphism analysis and direct sequencing. Seven types of missense gyrA mutations were observed in 70 of 335 strains (20.9%), and ciprofloxacin MICs were ≥3.13 μg/ml for 63 of 70 strains (90.0%). These included two double point mutations and three novel mutations (Ala-67→Ser plus Asp-87→Gly, Ala-84→Pro, and Gln-106→Leu). Thr-83→Ile mutants were predominantly observed (63 of 70 mutants) and showed high-level fluoroquinolone resistance (ciprofloxacin MIC at which 50% of isolates are inhibited, 25 μg/ml).


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiangke Duan ◽  
Yanrong Pan ◽  
Zhao Cai ◽  
Yumei Liu ◽  
Yingdan Zhang ◽  
...  

Abstract Background Pseudomonas aeruginosa is a notorious opportunistic pathogen causing various types of biofilm-related infections. Biofilm formation is a unique microbial strategy that allows P. aeruginosa to survive adverse conditions such as antibiotic treatment and human immune clearance. Results In this study, we experimentally evolved P. aeruginosa PAO1 biofilms for cyclic treatment in the presence of high dose of imipenem, and enriched hyperbiofilm mutants within six cycles in two independent lineages. The competition assay showed that the evolved hyperbiofilm mutants can outcompete the ancestral strain within biofilms but not in planktonic cultures. Whole-genome sequencing analysis revealed the hyperbiofilm phenotype is caused by point mutations in rpoS gene in all independently evolved mutants and the same mutation was found in P. aeruginosa clinical isolates. We further showed that mutation in rpoS gene increased the intracellular c-di-GMP level by turning on the expression of the diguanylate cyclases. Mutation in rpoS increased pyocyanin production and virulence in hyperbiofilm variants. Conclusion Here, our study revealed that antibiotic treatment of biofilm-related P. aeruginosa infections might induce a hyperbiofilm phenotype via rpoS mutation, which might partially explain antimicrobial treatment failure of many P. aeruginosa biofilm-related infections.


2020 ◽  
pp. 37-40

Genetic variety examination has demonstrated fundamental to the understanding of the epidemiological and developmental history of Papillomavirus (HPV), for the development of accurate diagnostic tests and for efficient vaccine design. The HPV nucleotide diversity has been investigated widely among high-risk HPV types. To make the nucleotide sequence of HPV and do the virus database in Thi-Qar province, and compare sequences of our isolates with previously described isolates from around the world and then draw its phylogenetic tree, this study done. A total of 6 breast formalin-fixed paraffin-embedded (FFPE) of the female patients were included in the study, divided as 4 FFPE malignant tumor and 2 FFPE of benign tumor. The PCR technique was implemented to detect the presence of HPV in breast tissue, and the real-time PCR used to determinant HPV genotypes, then determined a complete nucleotide sequence of HPV of L1 capsid gene, and draw its phylogenetic tree. The nucleotide sequencing finding detects a number of substitution mutation (SNPs) in (L1) gene, which have not been designated before, were identified once in this study population, and revealed that the HPV16 strains have the evolutionary relationship with the South African race, while, the HPV33 and HPV6 showing the evolutionary association with the North American and East Asian race, respectively.


2021 ◽  
Vol 43 (1) ◽  
Author(s):  
Kenichi Masumura ◽  
Tomoko Ando ◽  
Akiko Ukai ◽  
Sho Fujiwara ◽  
Shigeo Yokose ◽  
...  

Abstract Background Gene mutation assays in transgenic rodents are useful tools to investigate in vivo mutagenicity in a target tissue. Using a lambda EG10 transgene containing reporter genes, gpt delta transgenic mice and rats have been developed to detect point mutations and deletions. The transgene is integrated in the genome and can be rescued through an in vitro packaging reaction. However, the packaging efficiency is lower in gpt delta rats than in mice, because of the transgene in gpt delta rats being heterozygous and in low copy number. To improve the packaging efficiency, we herein describe a newly developed homozygous gpt delta rat strain. Results The new gpt delta rat has a Wistar Hannover background and has been successfully maintained as homozygous for the transgene. The packaging efficiency in the liver was 4 to 8 times higher than that of existing heterozygous F344 gpt delta rats. The frequency of gpt point mutations significantly increased in the liver and bone marrow of N-nitroso-N-ethylurea (ENU)- and benzo[a]pyrene (BaP)-treated rats. Spi− deletion frequencies significantly increased in the liver and bone marrow of BaP-treated rats but not in ENU-treated rats. Whole genome sequencing analysis identified ≥ 30 copies of lambda EG10 transgenes integrated in rat chromosome 1. Conclusions The new homozygous gpt delta rat strain showed a higher packaging efficiency, and could be useful for in vivo gene mutation assays in rats.


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