Genotypic characterization of toxigenic group C and G streptococci isolated in Chennai, South India

Abstract

Background & objectives: Increasing resistance to erythromycin has been observed worldwide in group C and group G streptococci (GCS/GGS). The information available from India is scanty. The aim of the study was to identify erythromycin resistant GCS/GGS isolates in Chennai, south India, and to compare erythromycin resistant genotypes with emm types. Methods: One hundred and thirty one GCS/GGS isolates were tested for erythromycin resistance by disc diffusion and agar dilution methods. Erythromycin resistance genotypes [ erm (A), erm (B) and mef (A)] were determined by a multiplex PCR. emm types of erythromycin resistant GCS/GGS isolates was also assessed using emm gene sequencing method. Results: Sixteen of the 131 isolates (12.21%) were resistant to erythromycin. Majority of the isolates were GGS (15/16). Eight of the 16 (50%) were S. dysgalactiae subsps. equisimilis . Twelve isolates (75%) were MLS B phenotype and four (25%) were M phenotype. Of the 12 isolates which exhibited MLS B resistance, seven showed cMLS B phenotype and were positive for erm (B) gene. The remaining five were iMLS B phenotype of which three were positive for erm (A) gene and two for erm (B) gene. erm (A) was common among carriers whereas erm (B) was common among clinical isolates. Interpretation & conclusions: MLS B was the predominant phenotype and erm (B) was the common genotype in the present study. The emm type stC1400.0 was frequently associated with erythromycin resistant GCS/GGS in our study.

Group C Streptococcus dysgalactiae subsp. equisimilis in south-east Brazil: genetic diversity, resistance profile and the first report of human and equine isolates belonging to the same multilocus sequence typing lineage

“…As reported previously, it has been verified that the M phenotype is linked to the mefA gene, which is involved in an active efflux pump system for 14-and 15-membered macrolides and lincosamines (Clancy et al, 1996), whilst the ermA gene is correlated with the iMLS B phenotype (Weisblum, 1995). A previous study (Prabu & Menon, 2013) reported rates of 9.2 and 3.1 % for the iMLS B and M phenotypes, respectively, which are similar to those found for our SDSE collection. Although ermB has been detected in other SDSE collections (Van Leer Buter et al, 2010;Prabu & Menon, 2013;Takahashi et al, 2011), the isolates from Brazil only harboured ermA, probably due to the high clonal structure of the collection.…”

“…A previous study (Prabu & Menon, 2013) reported rates of 9.2 and 3.1 % for the iMLS B and M phenotypes, respectively, which are similar to those found for our SDSE collection. Although ermB has been detected in other SDSE collections (Van Leer Buter et al, 2010;Prabu & Menon, 2013;Takahashi et al, 2011), the isolates from Brazil only harboured ermA, probably due to the high clonal structure of the collection.…”

“…Macrolide antibiotics are important therapeutic drugs in treating streptococcal infections, especially for patients with b-lactam hypersensitivity. The overall resistance rate to erythromycin in our study was similar to that reported in south India (12.2 %) for group C and G streptococci from humans (Prabu & Menon, 2013). However, a higher level of macrolide resistance (26.4 %) was detected for SDSE in France from 2006 to 2010 (Loubinoux et al, 2013).…”

“…Kirby-Bauer testing was performed according to the Clinical and Laboratory Standards Institute guidelines using Mueller-Hinton agar supplemented with 5 % defibrinated sheep blood (CLSI, 2014), and erythromycin (15 mg), clindamycin (2 mg), tetracycline (30 mg), levofloxacin (5 mg), chloramphenicol (30 mg), gentamicin (10 mg) and vancomycin (30 mg) discs (Cecon), incubated at 37 uC for 18 h. In addition, inducible clindamycin resistance was detected with a D test as described previously (Prabu & Menon, 2013). The MICs for the isolates that showed resistance to erythromycin and tetracycline were determined by the agar dilution method as recommended in the Clinical and Laboratory Standards Institute guidelines (CLSI, 2014) for concentration ranges of 0.015-124 and 0.5-64 mg?ml 21 , respectively.…”

Biotic and Abiotic Synthesis of Renewable Aliphatic Polyesters from Short Building Blocks Obtained from Biotechnology

“…[356] Coir pith, ah igh-lignin-content byproduct of coconut fibers, and thus, waste from the coir industry,c an be used as a carbon source by Azotobacter beijerinickii for P(3HB) biosynthesis. [357] Moreover, spent coffee grounds, aw idely available waste from coffee beverages, contain about 15 wt %o fv egetal oil, which can be simply extracted andc onverted into P(3HB) by C. necator. [358,359] Subsequently,h exose-rich spent coffee ground hydrolysates can be used by B. cepacia to produce P(3HB-co-3HV), with levulinic acid present in spent coffee grounds as the 3HV precursor.…”