Asunto(s)
Genoma Bacteriano , Listeria monocytogenes/genética , Listeria monocytogenes/inmunología , Listeriosis/microbiología , Serogrupo , Animales , Electroforesis en Gel de Campo Pulsado , Microbiología de Alimentos , Humanos , India/epidemiología , Larva/microbiología , Listeria monocytogenes/patogenicidad , Listeriosis/epidemiología , Listeriosis/transmisión , Mariposas Nocturnas/microbiología , Análisis de Secuencia de ADN , SerotipificaciónRESUMEN
In the present study, Salmonella isolates (n=40) recovered from clinical, food, poultry and environmental sources were characterized for serotype identification, genetic diversity and biofilm formation capability. Serotype identification using multiplex PCR assay revealed six isolates to be Salmonella Typhimurium, 14 as Salmonella Enteritidis, 11 as Salmonella Typhi, and the remaining nine isolates unidentified were considered as other Salmonella spp. Most of the Salmonella isolates (85%) produced biofilm on polystyrene surfaces as assessed by microtitre plate assay. About 67.5% isolates were weak biofilm producers and 17.5% were moderate biofilm producers. There was no significant difference in biofilm-forming ability among the Salmonella isolates recovered from different geographical regions or different sources. Among the genetic methods, Enterobacterial Repetitive Intergenic Consensus (ERIC) PCR revealed greater discriminatory power (DI, 0.943) followed by pulsed field gel electrophoresis (PFGE) (DI, 0.899) and random amplification of polymorphic DNA (RAPD) PCR (DI, 0.873). However, composite analysis revealed the highest discrimination index (0.957). Greater discrimination of S. Typhimurium and S. Typhi was achieved using PFGE, while ERIC PCR was better for S. Enteritidis and other Salmonella serotypes. A strong positive correlation (r=0.992) was observed between biofilm formation trait and clustered Salmonella isolates in composite genetic analysis.
Asunto(s)
Biopelículas , Microbiología Ambiental , Microbiología de Alimentos , Variación Genética , Salmonella/clasificación , Salmonella/fisiología , Animales , ADN Bacteriano/genética , Genotipo , Humanos , India , Tipificación de Secuencias Multilocus , Filogenia , Aves de Corral , Salmonella/aislamiento & purificación , SerotipificaciónRESUMEN
Group A rotaviruses can infect both humans and animals and have been recognized as an important cause of diarrhea in porcine. In this study, we report the prevalence and molecular epidemiology of rotaviruses detected in piglets in different regions of India. A total 275 fecal samples (180 diarrheal and 95 non-diarrheal) from piglets were collected from the western (135), southern (60), northern (20), and North-Eastern Hill (NEH) (60) regions of India and tested for rotaviruses. All the samples were subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and reverse transcription-polymerase chain reaction (RT-PCR). Rotaviruses were detected in 10.18 % of samples by SDS-PAGE and/or RT-PCR with a maximum of 30 % from the NEH region followed by 7.4 % from the western region. Samples from the southern and northern regions were found to be negative. Only 10 isolates were subjected to genotypic characterization using amplification of VP7 and VP4 genes followed by two separate multiplex PCR assays for G genotyping and another two for P genotyping using genotype-specific primers. Of these, three isolates could be typed as G4 specificity, one with G9, and three as P[6] leading to identification of an uncommon strain, G4P[6]. One isolate was further confirmed by nucleotide sequencing. The data demonstrate genetic diversity of porcine rotavirus strains and suggest that pig farms may serve as potential reservoirs for human infections.