1.Study on fluoroquinolone resistance and the relationship between resistance and mutations of gyrA and parC in Neisseria gonorrhoeae.
Jin-shui XU ; Bei WANG ; Chang-xian WANG ; Hai-jian GOU ; Zu-huang MI ; Jian-hua LING
Chinese Journal of Epidemiology 2006;27(8):702-704
OBJECTIVETo study the phenotypic and genotypic resistance to Fluoroquinolones in Neisseria gonorrhoeae (NG) isolated in Jiangsu province of China.
METHODSIn-vitro, susceptibility testing of ciprofloxacin and levofloxacin against ninety-five clinical isolates were determined by agar dilution method. Detection of mutation in the gyrA and parC genes was performed by polymerase chain reaction (PCR) assay and sequence analysis.
RESULTSThe clinical isolates demonstrated 100% resistance to ciprofloxacin. Based on gyrA and parC mutations, 18 types could be categorized among the 54 isolates. Based on the same gyrA mutations,isolates with high MIC appeared to have had more mutations in parC gene.
CONCLUSIONThe status of resistance to ciprofloxacin in NG was quite serious, and ciprofloxacin treatment for the treatment of NG infections in Jiangsu province should not be recommended. The results from this study suggested that mutations in the parC gene had contributed to the development of high Fluoroquinolone resistance in NG.
China ; DNA Gyrase ; genetics ; DNA Topoisomerase IV ; genetics ; Drug Resistance, Bacterial ; Fluoroquinolones ; pharmacology ; Genotype ; Gonorrhea ; drug therapy ; Humans ; Neisseria gonorrhoeae ; drug effects ; genetics ; isolation & purification ; Phenotype
2.Correlation between mutation of GyrA and ParC genes and quinolone resistance in Neisseria gonorrhoeae.
Ping XIE ; Zu-Huang MI ; Qin LI ; Ji ZHANG ; Chen-Yue XIAO
National Journal of Andrology 2003;9(4):275-278
OBJECTIVESTo investigate the correlation between mutation of GyrA and ParC genes and quinolone resistance in Neisseria Gonorrhoeae.
METHODSThe gene fragments of quinolone resistance-determining region (QRDR) in GyrA and ParC genes in 20 Neisseria gonorrhoeae strains clinically isolated in Wuxi, China, were sequenced, and the susceptibility of the 20 strains to quinolone was examined by agar diffusion method.
RESULTSThe mutations at the Asp95 point in GyrA gene were found in 20 strains. Of the 19 stains examined, 16 had mutations at the 86, 87, 88, 91 points in ParC genes.
CONCLUSIONSThe mutations of Asp95 in GyrA gene and Asp86, Ser87, Ser88, Glu91 in ParC gene contribute to quinolone resistance in Neisseria Gonorrhoeae.
Base Sequence ; DNA Gyrase ; genetics ; DNA Topoisomerase IV ; genetics ; Drug Resistance, Bacterial ; genetics ; Humans ; Molecular Sequence Data ; Mutation ; Neisseria gonorrhoeae ; drug effects ; genetics ; isolation & purification ; Quinolones ; pharmacology
3.A primary study on the relationship between amino acid mutations in clinical isolates of Neisseria gonorrhoeae and their resistance to antibiotics.
Gang YONG ; Dong-li WANG ; Yi TENG ; Sheng SHEN ; Jin QIU ; Zhi-mei XIE ; Xiao-fang PEI
Chinese Journal of Epidemiology 2007;28(3):273-276
OBJECTIVETo identify the relationship between amino acid mutations in Neisseria gonorrhoeae isolates and their antibiotic resistance.
METHODSPI gene fragments of Neisseria gonorrhoeae from 17 clinical isolates were obtained with PCR amplification. They were cloned into the PCR cloning vector pBS-T to form pBS-T-PI and sequenced. The sequences of PI genes were analyzed. At the same time, minimum inhibitory concentration (MIC) of penicillin and tetracycline to these 17 isolates were measured and contrasted with the corresponding PI sequence.
RESULTSThe recombinants of PI gene from 17 clinical isolates of Neisseria gonorrhoeae were successfully constructed and sequenced. They were divided into PIA and PIB subtypes according to the results from blastn software by comparing the sequences with the GenBank. Mutations were found at the sites of 120 and 121. There were only some of the sequences having an aspartic acid (D) mutation on 120 and 121 sites, which was not the same as reported. On the other hand,there were two PI sequences,5-9 and 6-1, whose mutations on No. 120 were lysine, similar to those documented.
CONCLUSIONSome relationship between PI amino acids mutations at sites 120 and 121 in Neisseria gonorrhoeae isolates from Chengdu, China and their resistance to penicillin and tetracycline were found. However,further studies need to be done in the future to confirm this hypothesis.
Amino Acid Sequence ; Anti-Bacterial Agents ; pharmacology ; DNA Mutational Analysis ; DNA, Bacterial ; Drug Resistance, Bacterial ; Mutation ; Neisseria gonorrhoeae ; drug effects ; genetics ; isolation & purification ; Polymerase Chain Reaction
4.Molecular characteristics of Neisseria gonorrhoeae isolates with decreased susceptibilities to ceftriaxone in Shenzhen from 2009 to 2011.
Li-jun ZHANG ; Jun-luan MO ; Feng WANG ; Yi PENG ; Guang-lu ZHAO ; De-liang LÜ
Chinese Journal of Preventive Medicine 2013;47(10):940-944
OBJECTIVETo investigate the genotype and characteristics of Neisseria gonorrhoeae (N.gonorrhoeae) isolates with reduced susceptibility to ceftriaxone in Shenzhen from 2009 to 2011.
METHODSA total of 296 N.gonorrhoeae isolates were collected in Shenzhen from 2009 to 2011.ceftriaxone strains (minimum inhibitory concentration between 0.06 and 0.50 µg/ml) were determined by agar dilution method.Logistic regression was used to analyze the associated factors of ceftriaxone N.gonorrhoeae infection.Neighbor-joining (NJ) phylogenetic tree analysis and N.gonorrhoeae multi antigen sequence typing (NG-MAST) were performed on all ceftriaxone isolates and susceptible control isolates randomly selected in accordance with the principle of 1: 1 sampling.
RESULTSNo isolates displayed resistance to ceftriaxone, whereas 53(17.9%) showed reduced susceptibility to ceftriaxone among 296 isolates.Only antibiotic use in recent two months was associated with ceftriaxone isolates infection (OR = 3.080, 95%CI: 1.376-6.894) . Among the ceftriaxone isolates, 48 different ST were identified including 5 STs (ST1768, ST3927, ST641, ST7076 and ST7078) containing 2 isolates and 43 single STs. There were 26 STs previously reported from HongKong in China.Low sensitive strains clustering was not observed by NJ phylogenetic tree.
CONCLUSIONThe proportion of ceftriaxone strains among the 296 N.gonorrhoeae isolates collected from 2009 to 2011 in Shenzhen is high. The STs of ceftriaxone strains may have unique epidemic features in Shenzhen.
Adult ; Anti-Bacterial Agents ; pharmacology ; Ceftriaxone ; pharmacology ; China ; epidemiology ; Drug Resistance, Bacterial ; genetics ; Female ; Gonorrhea ; epidemiology ; microbiology ; Humans ; Male ; Middle Aged ; Molecular Epidemiology ; Neisseria gonorrhoeae ; classification ; drug effects ; genetics ; isolation & purification ; Young Adult
5.Increasing Incidence of High-Level Tetracycline-Resistant Neisseria gonorrhoeae due to Clonal Spread and Foreign Import.
Hyukmin LEE ; Hyunsoo KIM ; Hyo Jin KIM ; Young Hee SUH ; Dongeun YONG ; Seok Hoon JEONG ; Kyungwon LEE ; Yunsop CHONG
Yonsei Medical Journal 2016;57(2):350-357
PURPOSE: The detection of high-level tetracycline-resistant strains of Neisseria gonorrhoeae (TRNG) can make important epidemiological contributions that are relevant to controlling infections from this pathogen. In this study, we aimed to determine the incidence of TRNG isolates over time and also to investigate the characteristics and genetic epidemiology of these TRNG isolates in Korea. MATERIALS AND METHODS: The antimicrobial susceptibilities of 601 isolates of N. gonorrhoeae from 2004 to 2011 were tested by standard Clinical and Laboratory Standards Institute methods. To determine the molecular epidemiological relatedness, N. gonorrhoeae multi-antigen sequence typing was performed. RESULTS: The incidence of TRNG increased from 2% in 2004 to 21% in 2011. The minimum inhibitory concentration distributions of ceftriaxone and susceptibility of ciprofloxacin in TRNG were different from non-TRNG and varied according to the year of isolation. Most of the TRNG isolates collected from 2004 to 2007 exhibited genetic relatedness, with sequence type (ST) 1798 being the most common. From 2008 to 2011, the STs of the isolates became more variable and introduction of genetically unrelated TRNG were noted. CONCLUSION: The increased incidence of TRNG strains until 2007 appears to be due, at least in part, to clonal spread. However, we propose that the emergence of various STs since 2008 could be associated with foreign import.
Anti-Bacterial Agents/*pharmacology
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Ceftriaxone/pharmacology
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Ciprofloxacin/pharmacology
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DNA, Bacterial/analysis
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Drug Resistance, Multiple, Bacterial/*genetics
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Gonorrhea/drug therapy/epidemiology/microbiology
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Humans
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Incidence
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Microbial Sensitivity Tests
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Molecular Epidemiology
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Neisseria gonorrhoeae/*drug effects/*genetics/isolation & purification
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Republic of Korea/epidemiology
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Sequence Analysis, DNA
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Tetracycline/pharmacology
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Tetracyclines/*pharmacology