scholarly journals Genetic antimicrobial resistance determinants and their prevalence in molecular subtypes of Treponema pallidum subsp. pallidum

2018 ◽  
Vol 20 (3) ◽  
pp. 216-221 ◽  
Author(s):  
O.A. Obraztsova ◽  
K.A. Aleynikova ◽  
A.P. Obukhov ◽  
A.A. Kubanov ◽  
Dmitry G. Deryabin
Keyword(s):  
Antimicrobial Resistance ◽  
16S Rrna ◽  
Russian Federation ◽  
Molecular Subtypes ◽  
Treponema Pallidum ◽  
Clinical Isolates ◽  
23S Rrna ◽  
Rrna Gene ◽  
Genetic Determinants ◽  
The Russian Federation

Objective. To investigate genetic determinants of resistance to antimicrobial agents recommended for the treatment of syphilis and assess their prevalence in molecular subtypes of Treponema pallidum subsp. pallidum in the Russian Federation over the period of 2014-2017. Materials and Methods. A total of 161 clinical isolates of T. pallidum obtained from Tyva, Stavropol, Irkutsk, Kaluga, Novosibirsk and Omsk regions were included in this study. Genetic material of T. pallidum was detected by PCR with primers to polA gene. Determinants of resistance to penicillins (tromp1, tp47), tetracyclines (16S rRNA) and macrolides (23S rRNA) were determined using the gene sequence analysis. Molecular typing was performed by characterizing variable arp, tpr (E, G, J) and tp0548 genes according to the CDC protocol. Results of this study were compared to historical data on antimicrobial resistance of T. pallidum over the period of 2011-2012. Results. Analysis of tromp1 and tp47 gene sequences detected C22G and G208T substitutions, respectively. These polymorphisms were not significant for activity of the corresponding proteins, but differed the studied clinical isolates from the reference strain Nichols, therefore, linking them with epidemic genogroup T. pallidum Street Strain 14. Based on the analysis of G1058C mutation in the 16S rRNA gene, all clinical isolates obtained in 2014-2017 belonged to wild type, whereas this genetic determinant of resistance to tetracyclines was determined in 2 of 190 isolates obtained in 2011-2012. Also, A2059G/C mutation in the 23S rRNA gene was not found, whereas a significant A2058G substitution in this gene was determined in 4 isolates obtained in 2014-2017. Results of this study confirm sporadic resistance to macrolides in the Russian Federation, which was previously (2011-2012) found in 3 of 190 isolates of T. pallidum. A2058G mutation was detected predominantly in minor subtypes of T. pallidum (14 b/f, 14 b/g and 14 d/g) and was unrepresentative for molecular subtype 14 d/f which is a predominant one in the Russian Federation. Conclusions. The long-term use of penicillins for the treatment of syphilis did not result in emergence of T. pallidum resistance to this antibiotic class. An absence of genetic determinants of resistance to tetracyclines confirms them to be second-line drugs. A sporadic prevalence of determinants of resistance to macrolides requires they be used for the treatment of syphilis with caution.

scholarly journals Comparison of Genospecies and Antimicrobial Resistance Profiles of Isolates in the Acinetobacter calcoaceticus-Acinetobacter baumannii Complex from Various Clinical Specimens

2012 ◽  
Vol 56 (12) ◽  
pp. 6267-6271 ◽  
Author(s):  
Ni Tien ◽  
Bang-Jau You ◽  
Hui-Lan Chang ◽  
Hsiu-Shen Lin ◽  
Chin-Yi Lee ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Acinetobacter Baumannii ◽  
Restriction Analysis ◽  
Acinetobacter Calcoaceticus ◽  
Its Region ◽  
Clinical Isolates ◽  
23S Rrna ◽  
Rrna Gene ◽  
Genotype 3 ◽  
Content Type

ABSTRACTThis study was conducted to compare the prevalences of antimicrobial resistance profiles of clinical isolates in theAcinetobacter calcoaceticus-Acinetobacter baumanniicomplex from sterile and nonsterile sites and to further study the relationship of antimicrobial resistance profiles and genospecies by amplified rRNA gene restriction analysis (ARDRA). A total of 1,381 isolates were tested with 12 different antibiotics to show their antimicrobial susceptibility profiles. A total of 205 clinical isolates were further analyzed by ARDRA of the intergenic spacer (ITS) region of the 16S-23S rRNA gene. It was found that the overall percentage of isolates from nonsterile sites (urine, sputum, pus, or catheter tip) that were resistant to the 12 antibiotics tested was significantly higher than that of isolates from sterile sites (cerebrospinal fluid [CSF], ascites fluid, and bloodstream) (46% versus 22%;P< 0.05). After ARDRA, it was found that 97% of the 62 isolates resistant to all antibiotics tested were theA. baumanniigenospecies, which was identified in only 31% of the isolates susceptible to all antibiotics tested. More genospecies diversity was identified in the isolates susceptible to all antibiotics tested, including genospecies of 13TU (34%), genotype 3 (29%), andA. calcoaceticus(5%). Furthermore, as 91% (10/11) of the isolates from CSF were susceptible to all antibiotics tested, theA. calcoaceticus-A. baumanniicomplex isolates with multidrug resistance could be less invasive than the more susceptible isolates. This study also indicated current emergence of carbapenem-, fluoroquinolone-, aminoglycoside-, and cephalosporin-resistantA. calcoaceticus-A. baumanniicomplex isolates in Taiwan.

scholarly journals Detection of Kanamycin-ResistantMycobacterium tuberculosis by Identifying Mutations in the 16S rRNA Gene

1998 ◽  
Vol 36 (5) ◽  
pp. 1220-1225 ◽  
Author(s):  
Yasuhiko Suzuki ◽  
Chihiro Katsukawa ◽  
Aki Tamaru ◽  
Chiyoji Abe ◽  
Masanao Makino ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Direct Sequencing ◽  
Clinical Isolates ◽  
23S Rrna ◽  
Rrna Gene ◽  
Double Mutation ◽  
Resistant Strains ◽  
Type Strains ◽  
The 16S Rrna Gene

In Mycobacterium smegmatis and a limited number ofMycobacterium tuberculosis strains, the involvement of alterations of the 16S rRNA gene (rrs) in resistance to kanamycin has been shown. To investigate the extent to which mutations in a specific region of the rrs gene and the kanamycin-resistant phenotype in clinically isolated M. tuberculosis strains were correlated, 43 kanamycin-resistant strains (MICs, ≧200 μg/ml), 71 kanamycin-susceptible strains, and 4 type strains were examined. The 300-bp DNA fragments carrying therrs gene and the intervening sequence between therrs gene and 23S rRNA (rrl) gene fragments were amplified by PCR and were subjected to PCR-based direct sequencing. By comparing the nucleotide sequences, substitutions were found in 29 of 43 (67.4%) kanamycin-resistant clinical isolates at positions 1400, 1401, and 1483 but in none of the 71 sensitive isolates or the 4 type strains. The most frequent substitution, from A to G, occurred at position 1400. A substitution from C to T at position 1401 was found once. Two clinical isolates carried the double mutation from C to A at position 1401 and from G to T at position 1483. In addition, we found that these mutants can be distinguished from wild-type strains by digestion with the restriction endonucleases TaiI andTsp45I. Furthermore, we found that the genotypes of kanamycin-resistant strains can be discriminated from each other by digestion with a restriction endonuclease, BstUI orDdeI.

scholarly journals Development of a Microelectronic Chip Array for High-Throughput Genotyping of Helicobacter Species and Screening for Antimicrobial Resistance

2005 ◽  
Vol 10 (3) ◽  
pp. 235-245 ◽  
Author(s):  
James Z. Xing ◽  
Chris Clarke ◽  
Lijun Zhu ◽  
Stephan Gabos
Keyword(s):  
Antimicrobial Resistance ◽  
16S Rrna ◽  
Tetracycline Resistance ◽  
Rrna Genes ◽  
23S Rrna ◽  
Rrna Gene ◽  
Nucleotide Polymorphisms ◽  
23S Rrna Gene ◽  
23S Rrna Genes ◽  
H Pylori

A microelectronic array assay was developed to specifically genotype Helicobacter pylori versus Helicobacter heilmannii and to determine antimicrobial resistance. Helicobacter 16S rRNA and 23S rRNA genes were specifically generated with Helicobacter genus-specific primers, respectively. The single-nucleotide polymorphisms (SNPs) in 16S rRNA, 268T specific in the H. pylori sequence, and 263A specific in H. heilmannii were used as molecular markers for identification of H. pylori and H. heilmannii, respectively. A triple-base-pair resistant mutation, AGA965-967TTC in 16S rRNA, is known to be responsible for H. pylori tetracycline resistance and was detected to identify resistant strains. H. pylori macrolide resistance was determined by the identification of 3 defined mutations in the 23S rRNA gene using the same method. The assay could be directly used to detect H. pylori in feces. The assay performs multiple determinations, including identification of Helicobacter species and antibiotic resistances, on the same microelectronic platform and is highly amenable to the development of other DNA-based assays.

scholarly journals Association between 16S rRNA gene mutations and susceptibility to amikacin in Mycobacterium avium Complex and Mycobacterium abscessus clinical isolates

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Su-Young Kim ◽  
Dae Hun Kim ◽  
Seong Mi Moon ◽  
Ju Yeun Song ◽  
Hee Jae Huh ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Mycobacterium Avium ◽  
Inhibitory Concentration ◽  
Gene Mutations ◽  
Mycobacterium Abscessus ◽  
Clinical Isolates ◽  
Rrna Gene ◽  
High Level ◽  
Culture Conversion

AbstractWe evaluated the association between 16S rRNA gene (rrs) mutations and susceptibility in clinical isolates of amikacin-resistant nontuberculous mycobacteria (NTM) in NTM-pulmonary disease (PD) patients. Susceptibility was retested for 134 amikacin-resistant isolates (minimum inhibitory concentration [MIC] ≥ 64 µg/ml) from 86 patients. Amikacin resistance was reconfirmed in 102 NTM isolates from 62 patients with either Mycobacterium avium complex-PD (MAC-PD) (n = 54) or M. abscessus-PD (n = 8). MICs and rrs mutations were evaluated for 318 single colonies from these isolates. For the 54 MAC-PD patients, rrs mutations were present in 34 isolates (63%), comprising all 31 isolates with amikacin MICs ≥ 128 µg/ml, but only three of 23 isolates with an MIC = 64 µg/ml. For the eight M. abscessus-PD patients, all amikacin-resistant (MIC ≥ 64 µg/ml) isolates had rrs mutations. In amikacin-resistant isolates, the A1408G mutation (n = 29) was most common. Two novel mutations, C1496T and T1498A, were also identified. The culture conversion rate did not differ by amikacin MIC. Overall, all high-level and 13% (3/23) of low-level amikacin-resistant MAC isolates had rrs mutations whereas mutations were present in all amikacin-resistant M. abscessus isolates. These findings are valuable for managing MAC- and M. abscessus-PD and suggest the importance of phenotypic and genotypic susceptibility testing.

Prevalence and Antimicrobial Resistance of Campylobacter spp. Isolated from Poultry Carcasses in Poland

2013 ◽  
Vol 76 (8) ◽  
pp. 1451-1455 ◽  
Author(s):  
KINGA WIECZOREK ◽  
IWONA KANIA ◽  
JACEK OSEK
Keyword(s):  
Campylobacter Jejuni ◽  
23S Rrna ◽  
Rrna Gene ◽  
Campylobacter Coli ◽  
Genetic Determinants ◽  
Gyra Gene ◽  
23S Rrna Gene ◽  
Pcr Method ◽  
Almost All ◽  
Campylobacter Spp

The purpose of the present study was to determine the prevalence of Campylobacter in poultry carcasses at slaughter in Poland. For the isolated strains, resistance to selected antibiotics and the associated genetic determinants were identified. A total of 498 Campylobacter isolates were obtained from 802 poultry samples during the 2-year study period. Strains were identified to species with the PCR method; 53.6% of the strains were Campylobacter jejuni and 46.4% were Campylobacter coli. A high percentage of the tested Campylobacter strains were resistant to ciprofloxacin and nalidixic acid (74.1 and 73.5%, respectively) followed by tetracycline (47.4%) and streptomycin (20.5%). Only one C. jejuni and two C. coli isolates were resistant to gentamicin. Seventy-nine (15.9%) of the 498 strains were resistant to three or more classes of antibiotics examined. Higher levels of resistance, irrespective of the antimicrobial agent tested, were found within the C. coli group. Almost all strains resistant to quinolones (99.5%) and to tetracycline (99.6%) carried the Thr-86-to-Ile mutation in the gyrA gene and possessed the tet(O) marker, respectively. All isolates resistant to erythromycin had the A2075G mutation in the 23S rRNA gene. These results reveal that poultry carcasses in Poland are a reservoir of potentially pathogenic and antimicrobial-resistant Campylobacter strains for humans, which may pose a public health risk.

scholarly journals Leptospira Survey in Wild Boar (Sus scrofa) Hunted in Tuscany, Central Italy

Pathogens ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 377 ◽  
Author(s):  
Giovanni Cilia ◽  
Fabrizio Bertelloni ◽  
Marta Angelini ◽  
Domenico Cerri ◽  
Filippo Fratini
Keyword(s):  
16S Rrna ◽  
Wild Boar ◽  
Sus Scrofa ◽  
Central Italy ◽  
23S Rrna ◽  
Rrna Gene ◽  
Pathogenic Leptospira ◽  
Molecular Assays ◽  
Realtime Pcr ◽  
23S Rrna Gene

Leptospirosis is a re-emerging, worldwide zoonosis, and wild boar (Sus scrofa) are involved in its epidemiology as the reservoir. The aim of this study was to investigate the prevalence of Leptospira with serological, bacteriological, and molecular assays in wild boar hunted in Tuscany (Italy) during two hunting seasons. In total, 287 specimens of sera, kidneys, and liver were collected to perform microscopic agglutination tests (MATs), isolation, and RealTime PCR to detect pathogenic (lipL32 gene), intermediate (16S rRNA gene), and saprophytic (23S rRNA gene) Leptospira. Within sera, 39 (13.59%) were positive to the MAT, and Australis was the most represented serogroup (4.88%), followed by Pomona (4.18%), and Tarassovi (3.14%). Moreover, four Leptospira cultures were positive, and once isolates were identified, one was identified as L. borgpetersenii serovar Tarassovi, and three as L. interrogans serovar Bratislava. Pathogenic Leptospira DNA were detected in 32 wild boar kidneys (11.15%). The characterization through the amplification of the rrs2 gene highlighted their belonging to L. interrogans (23 kidneys), L. borgpetersenii (four), and L. kirschneri (one), while nine kidneys (3.14%) were positive for intermediate Leptospira, all belonging to L. fainei. The results of this study confirmed the importance of wild boar in the epidemiology of leptospirosis among wildlife in Central Italy.

scholarly journals A New ‘Candidatus Liberibacter’ Species Associated with Diseases of Solanaceous Crops

Plant Disease ◽  
2009 ◽  
Vol 93 (3) ◽  
pp. 208-214 ◽  
Author(s):  
Lia W. Liefting ◽  
Paul W. Sutherland ◽  
Lisa I. Ward ◽  
Kerry L. Paice ◽  
Bevan S. Weir ◽  
...  
Keyword(s):  
16S Rrna ◽  
Pcr Primers ◽  
23S Rrna ◽  
Rrna Gene ◽  
High Identity ◽  
Specific Pcr ◽  
Transmission Electron ◽  
Candidatus Liberibacter ◽  
Polymerase Chain ◽  
Specific Pcr Primer

A new disease of glasshouse-grown tomato and pepper in New Zealand has resulted in plant decline and yield loss. Affected plants are characterized by spiky, chlorotic apical growth, curling or cupping of the leaves, and overall stunting. Transmission electron microscopy revealed the presence of phloem-limited bacterium-like organisms in symptomatic plants. The strategy used to identify the bacterium involved using specific prokaryote polymerase chain reaction (PCR) primers in combination with universal 16S rRNA primers. Sequence analysis of the 16S rRNA gene, the 16S/23S rRNA spacer region, and the rplKAJL-rpoBC operon revealed that the bacterium shared high identity with ‘Candidatus Liberibacter’ species. Phylogenetic analysis showed that the bacterium is distinct from the three citrus liberibacter species previously described and has been named ‘Candidatus Liberibacter solanacearum’. This is the first report of a liberibacter naturally infecting a host outside the Rutaceae family. A specific PCR primer pair was developed for its detection.

scholarly journals Rarimicrobium hominis gen. nov., sp. nov., representing the fifth genus in the phylum Synergistetes that includes human clinical isolates

2015 ◽  
Vol 65 (Pt_11) ◽  
pp. 3965-3970 ◽  
Author(s):  
Estelle Jumas-Bilak ◽  
Philippe Bouvet ◽  
Emma Allen-Vercoe ◽  
Fabien Aujoulat ◽  
Paul A. Lawson ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Type Strain ◽  
Gene Sequence ◽  
Sequence Similarity ◽  
Clinical Isolates ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
Strictly Anaerobic ◽  
Rrna Gene Sequence

Five human clinical isolates of an unknown, strictly anaerobic, slow-growing, Gram-stain-negative, rod-shaped micro-organism were subjected to a polyphasic taxonomic study. Comparative 16S rRNA gene sequence-based phylogeny showed that the isolates grouped in a clade that included members of the genera Pyramidobacter, Jonquetella, and Dethiosulfovibrio; the type strain of Pyramidobacter piscolens was the closest relative with 91.5–91.7 % 16S rRNA gene sequence similarity. The novel strains were mainly asaccharolytic and unreactive in most conventional biochemical tests. Major metabolic end products in trypticase/glucose/yeast extract broth were acetic acid and propionic acid and the major cellular fatty acids were C13 : 0 and C16 : 0, each of which could be used to differentiate the strains from P. piscolens. The DNA G+C content based on whole genome sequencing for the reference strain 22-5-S 12D6FAA was 57 mol%. Based on these data, a new genus, Rarimicrobium gen. nov., is proposed with one novel species, Rarimicrobium hominis sp. nov., named after the exclusive and rare finding of the taxon in human samples. Rarimicrobium is the fifth genus of the 14 currently characterized in the phylum Synergistetes and the third one in subdivision B that includes human isolates. The type strain of Rarimicrobium hominis is ADV70T ( = LMG 28163T = CCUG 65426T).

Taxonomic study of the genus Salinicola: transfer of Halomonas salaria and Chromohalobacter salarius to the genus Salinicola as Salinicola salarius comb. nov. and Salinicola halophilus nom. nov., respectively

2010 ◽  
Vol 60 (4) ◽  
pp. 963-971 ◽  
Author(s):  
Rafael R. de la Haba ◽  
Cristina Sánchez-Porro ◽  
M. Carmen Márquez ◽  
Antonio Ventosa
Keyword(s):  
16S Rrna ◽  
Type Strain ◽  
Phylogenetic Trees ◽  
23S Rrna ◽  
Rrna Gene ◽  
Gene Sequences ◽  
The Family ◽  
23S Rrna Gene ◽  
Single Genus ◽  
Type Strains

We have carried out a polyphasic taxonomic characterization of the type strains of the species with the recently validated name Salinicola socius, together with two species that were phylogenetically closely related, Halomonas salaria and Chromohalobacter salarius. 16S rRNA gene sequence analyses showed that they constituted a coherent cluster, with sequence similarities between 98.7 and 97.7 %. We have determined the almost complete 23S rRNA gene sequences of these three type strains, and the percentage of similarity between them was 99.2–97.6 %. Phylogenetic trees based on the 16S rRNA and 23S rRNA gene sequences, obtained by using three different algorithms, were consistent and showed that these three species constituted a cluster separated from the other species of the genera of the family Halomonadaceae, supporting their placement in a single genus. All three species have ubiquinone 9 as the major respiratory quinone, and showed similar fatty acid and polar lipid profiles. The level of DNA–DNA hybridization between Salinicola socius DSM 19940T, Halomonas salaria DSM 18044T and Chromohalobacter salarius CECT 5903T was 41–21 %, indicating that they are different species of the genus Salinicola. A comparative phenotypic study of these strains following the proposed minimal standards for describing new taxa of the family Halomonadaceae has been carried out. The phenotypic data are consistent with the placement of these three species in a single genus and support their differentiation at the species level. On the basis of these data we have emended the description of the species Salinicola socius and we propose to transfer the species Halomonas salaria and Chromohalobacter salarius to the genus Salinicola, as Salinicola salarius comb. nov. (type strain M27T =KCTC 12664T =DSM 18044T) and Salinicola halophilus nom. nov. (type strain CG4.1T =CECT 5903T =LMG 23626T), respectively.

scholarly journals Sporosarcina newyorkensis sp. nov. from clinical specimens and raw cow’s milk

2012 ◽  
Vol 62 (2) ◽  
pp. 322-329 ◽  
Author(s):  
William J. Wolfgang ◽  
An Coorevits ◽  
Jocelyn A. Cole ◽  
Paul De Vos ◽  
Michelle C. Dickinson ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
New York State ◽  
23S Rrna ◽  
Rrna Gene ◽  
The Novel ◽  
Gene Sequences ◽  
16S Rrna Gene Sequences ◽  
Clinical Specimens ◽  
The 16S Rrna Gene

Twelve independent isolates of a Gram-positive, endospore-forming rod were recovered from clinical specimens in New York State, USA, and from raw milk in Flanders, Belgium. The 16S rRNA gene sequences for all isolates were identical. The closest species with a validly published name, based on 16S rRNA gene sequence, is Sporosarcina koreensis (97.13 % similarity). DNA–DNA hybridization studies demonstrate that the new isolates belong to a species distinct from their nearest phylogenetic neighbours. The partial sequences of the 23S rRNA gene for the novel strains and their nearest neighbours also provide support for the novel species designation. Maximum-likelihood phylogenetic analysis of the 16S rRNA gene sequences confirmed that the new isolates are in the genus Sporosarcina. The predominant menaquinone is MK-7, the peptidoglycan has the type A4α l-Lys–Gly–d-Glu, and the polar lipids consist of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The predominant fatty acids are iso-C14 : 0, iso-C15 : 0 and anteiso-C15 : 0. In addition, biochemical and morphological analyses support designation of the twelve isolates as representatives of a single new species within the genus Sporosarcina, for which the name Sporosarcina newyorkensis sp. nov. (type strain 6062T  = DSM 23544T  = CCUG 59649T  = LMG 26022T) is proposed.

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