BIOMAT Database Logo BIOMAT Database Logo

Shiga Toxin Subtypes of Non-O157 Escherichia coli Serogroups Isolated from Cattle Feces. 2017

Pragathi B Shridhar, and Chris Siepker, and Lance W Noll, and Xiaorong Shi, and T G Nagaraja, and Jianfa Bai
Department of Diagnostic Medicine and Pathobiology, Kansas State UniversityManhattan, KS, USA.

Shiga toxin producing Escherichia coli (STEC) are important foodborne pathogens responsible for human illnesses. Cattle are a major reservoir that harbor the organism in the hindgut and shed in the feces. Shiga toxins (Stx) are the primary virulence factors associated with STEC illnesses. The two antigenically distinct Stx types, Stx1 and Stx2, encoded by stx1 and stx2 genes, share approximately 56% amino acid sequence identity. Genetic variants exist within Stx1 and Stx2 based on differences in amino acid composition and in cytotoxicity. The objective of our study was to identify the stx subtypes in strains of STEC serogroups, other than O157, isolated from cattle feces. Shiga toxin gene carrying E. coli strains (n = 192), spanning 27 serogroups originating from cattle (n = 170) and human (n = 22) sources, were utilized in the study. Shiga toxin genes were amplified by PCR, sequenced, and nucleotide sequences were translated into amino acid sequences using CLC main workbench software. Shiga toxin subtypes were identified based on the amino acid motifs that define each subtype. Shiga toxin genotypes were also identified at the nucleotide level by in silico restriction fragment length polymorphism (RFLP). Of the total 192 STEC strains, 93 (48.4%) were positive for stx1 only, 43 (22.4%) for stx2 only, and 56 (29.2%) for both stx1 and stx2. Among the 149 strains positive for stx1, 132 (88.6%) were stx1a and 17 (11.4%) were stx1c. Shiga toxin 1a was the most common subtype of stx1 among cattle (87.9%; 123/140) and human strains (100%; 9/9) of non-O157 serogroups. Of the total 99 strains positive for stx2, 79 were stx2a (79.8%), 11 (11.1%) were stx2c, 12 (12.1%) were stx2d. Of the 170 strains originating from cattle feces, 58 (34.1%) were stx2a subtype, 11 (6.5%) were stx2c subtype, and 11 were of subtype stx2d (6.5%). All but one of the human strains were positive for stx2a. Three strains of cattle origin were positive for both stx2a and stx2d. In conclusion, a number of non-O157 STEC serogroups harbored by cattle possess a wide variety of Shiga toxin subtypes, with stx1a and stx2a being the most predominant stx subtypes occurring individually or in combination. Cattle are a reservoir of a number of non-O157 STEC serogroups and information on the Shiga toxin subtypes is useful in assessing the potential risk as human pathogens.

UI MeSH Term Description Entries
D012150 Polymorphism, Restriction Fragment Length Variation occurring within a species in the presence or length of DNA fragment generated by a specific endonuclease at a specific site in the genome. Such variations are generated by mutations that create or abolish recognition sites for these enzymes or change the length of the fragment. RFLP,Restriction Fragment Length Polymorphism,RFLPs,Restriction Fragment Length Polymorphisms
D002417 Cattle Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor. Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D004926 Escherichia coli A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc. Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D004927 Escherichia coli Infections Infections with bacteria of the species ESCHERICHIA COLI. E coli Infections,E. coli Infection,Infections, E coli,Infections, Escherichia coli,E coli Infection,E. coli Infections,Escherichia coli Infection,Infection, E coli,Infection, E. coli,Infection, Escherichia coli
D005243 Feces Excrement from the INTESTINES, containing unabsorbed solids, waste products, secretions, and BACTERIA of the DIGESTIVE SYSTEM.
D005838 Genotype The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS. Genogroup,Genogroups,Genotypes
D006801 Humans Members of the species Homo sapiens. Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D016133 Polymerase Chain Reaction In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships. Anchored PCR,Inverse PCR,Nested PCR,PCR,Anchored Polymerase Chain Reaction,Inverse Polymerase Chain Reaction,Nested Polymerase Chain Reaction,PCR, Anchored,PCR, Inverse,PCR, Nested,Polymerase Chain Reactions,Reaction, Polymerase Chain,Reactions, Polymerase Chain
D017422 Sequence Analysis, DNA A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis. DNA Sequence Analysis,Sequence Determination, DNA,Analysis, DNA Sequence,DNA Sequence Determination,DNA Sequence Determinations,DNA Sequencing,Determination, DNA Sequence,Determinations, DNA Sequence,Sequence Determinations, DNA,Analyses, DNA Sequence,DNA Sequence Analyses,Sequence Analyses, DNA,Sequencing, DNA

Related Publications

Pragathi B Shridhar, and Chris Siepker, and Lance W Noll, and Xiaorong Shi, and T G Nagaraja, and Jianfa Bai
Identification, Shiga toxin subtypes and prevalence of minor serogroups of Shiga toxin-producing Escherichia coli in feedlot cattle feces.
April 2021, Scientific reports,
Pragathi B Shridhar, and Chris Siepker, and Lance W Noll, and Xiaorong Shi, and T G Nagaraja, and Jianfa Bai
Novel sequence types of non-O157 Shiga toxin-producing Escherichia coli isolated from cattle.
June 2015, Letters in applied microbiology,
Pragathi B Shridhar, and Chris Siepker, and Lance W Noll, and Xiaorong Shi, and T G Nagaraja, and Jianfa Bai
Virulence genes, Shiga toxin subtypes, major O-serogroups, and phylogenetic background of Shiga toxin-producing Escherichia coli strains isolated from cattle in Iran.
August 2017, Microbial pathogenesis,
Pragathi B Shridhar, and Chris Siepker, and Lance W Noll, and Xiaorong Shi, and T G Nagaraja, and Jianfa Bai
Shiga Toxin Subtypes and Virulence Genes in Escherichia coli Isolated from Cattle.
March 2017, Japanese journal of infectious diseases,
Pragathi B Shridhar, and Chris Siepker, and Lance W Noll, and Xiaorong Shi, and T G Nagaraja, and Jianfa Bai
Diversity of Non-O157 Shiga Toxin-Producing Escherichia coli Isolated from Cattle from Central and Southern Chile.
August 2021, Animals : an open access journal from MDPI,
Pragathi B Shridhar, and Chris Siepker, and Lance W Noll, and Xiaorong Shi, and T G Nagaraja, and Jianfa Bai
A Comparison of Culture- and PCR-Based Methods to Detect Six Major Non-O157 Serogroups of Shiga Toxin-Producing Escherichia coli in Cattle Feces.
January 2015, PloS one,
Pragathi B Shridhar, and Chris Siepker, and Lance W Noll, and Xiaorong Shi, and T G Nagaraja, and Jianfa Bai
Non-O157 Shiga-toxin-producing Escherichia coli.
January 2012, The Lancet. Infectious diseases,
Pragathi B Shridhar, and Chris Siepker, and Lance W Noll, and Xiaorong Shi, and T G Nagaraja, and Jianfa Bai
Genomic analysis of shiga toxin-containing Escherichia coli O157:H7 isolated from Argentinean cattle.
January 2021, PloS one,
Pragathi B Shridhar, and Chris Siepker, and Lance W Noll, and Xiaorong Shi, and T G Nagaraja, and Jianfa Bai
Characterization of non-Shiga-toxin-producing Escherichia coli O157 strains isolated from dogs.
January 2010, Revista Argentina de microbiologia,
Pragathi B Shridhar, and Chris Siepker, and Lance W Noll, and Xiaorong Shi, and T G Nagaraja, and Jianfa Bai
Feces of feedlot cattle contain a diversity of bacteriophages that lyse non-O157 Shiga toxin-producing Escherichia coli.
July 2015, Canadian journal of microbiology,
Copied contents to your clipboard!