scholarly journals Molecular Analysis of the rfb O Antigen Gene Cluster of Salmonella enterica Serogroup O:6,14 and Development of a Serogroup-Specific PCR Assay

2003 ◽  
Vol 69 (10) ◽  
pp. 6099-6105 ◽  
Author(s):  
Collette Fitzgerald ◽  
Rachel Sherwood ◽  
Linda L. Gheesling ◽  
Frances W. Brenner ◽  
Patricia I. Fields
Keyword(s):  
Gene Cluster ◽  
Sequence Similarity ◽  
Rapid Identification ◽  
Homologous Sequence ◽  
Pcr Assay ◽  
Typing Method ◽  
Specific Test ◽  
O Antigen ◽  
Specific Pcr ◽  
Specific Pcr Assay

ABSTRACT The Kauffmann-White scheme for serotyping Salmonella recognizes 46 somatic (O) antigen groups, which together with detection of the flagellar (H) antigens form the basis for serotype identification. Although serotyping has become an invaluable typing method for epidemiological investigations of Salmonella, it does have some practical limitations. We have been characterizing the genes required for O and H antigen biosynthesis with the goal of developing a DNA-based system for the determination of serotype in Salmonella. The majority of the enzymes involved in O antigen biosynthesis are encoded by the rfb gene cluster. We report the sequencing of the rfb region from S. enterica serotype Sundsvall (serogroup O:6,14). The S. enterica serotype Sundsvall rfb region is 8.4 kb in length and comprises six open reading frames. When compared with other previously characterized rfb regions, the serogroup O:6,14 sequence is most related to serogroup C1. On the basis of DNA sequence similarity, we identified two genes from the mannose biosynthetic pathway, two mannosyl transferase genes, the O unit flippase gene and, possibly, the O antigen polymerase. The whole cluster is derived from a low-G+C-content organism. Comparative sequencing of an additional serogroup O:6,14 isolate (S. enterica serotype Carrau) revealed a highly homologous sequence, suggesting that O antigen factors O:24 and O:25 (additional O factors associated with serogroup O:6,14) are encoded outside the rfb gene cluster. We developed a serogroup O:6,14-specific PCR assay based on a region of the putative wzx (O antigen flippase) gene. This provides the basis for a sensitive and specific test for the rapid identification of Salmonella serogroup O:6,14.

scholarly journals Structural and Genetic Characterization of Enterohemorrhagic Escherichia coli O145 O Antigen and Development of an O145 Serogroup-Specific PCR Assay

2005 ◽  
Vol 187 (2) ◽  
pp. 758-764 ◽  
Author(s):  
Lu Feng ◽  
Sof'ya N. Senchenkova ◽  
Jiang Tao ◽  
Alexander S. Shashkov ◽  
Bin Liu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Gene Cluster ◽  
Antigen Processing ◽  
Enterohemorrhagic Escherichia Coli ◽  
Open Reading Frames ◽  
Pcr Assay ◽  
E Coli ◽  
O Antigen ◽  
Specific Pcr ◽  
Specific Pcr Assay

ABSTRACT Enterohemorrhagic Escherichia coli O145 strains are emerging as causes of hemorrhagic colitis and hemolytic uremic syndrome. In this study, we present the structure of the E. coli O145 O antigen and the sequence of its gene cluster. The O145 antigen has repeat units containing three monosaccharide residues: 2-acetamido-2-deoxy-d-glucose (GlcNAc), 2-acetamidoylamino-2,6-dideoxy-l-galactose, and N-acetylneuraminic acid. It is very closely related to Salmonella enterica serovar Touera and S. enterica subsp. arizonae O21 antigen. The E. coli O145 gene cluster is located between the JUMPStart sequence and the gnd gene and consists of 15 open reading frames. Putative genes for the synthesis of the O-antigen constituents, for sugar transferase, and for O-antigen processing were annotated based on sequence similarities and the presence of conserved regions. The putative genes located in the E. coli O145 O-antigen gene cluster accounted for all functions expected for synthesis of the structure. An E. coli O145 serogroup-specific PCR assay based on the genes wzx and wzy was also developed by screening E. coli and Shigella isolates of different serotypes.

scholarly journals Molecular Cloning and Sequencing of thearoA Gene from Actinobacillus pleuropneumoniaeand Its Use in a PCR Assay for Rapid Identification

1999 ◽  
Vol 37 (5) ◽  
pp. 1575-1578 ◽  
Author(s):  
Carmen Hernanz Moral ◽  
Alberto Cascón Soriano ◽  
María Sánchez Salazar ◽  
Javier Yugueros Marcos ◽  
Susana Suárez Ramos ◽  
...  
Keyword(s):  
Rapid Identification ◽  
Chromosomal Dna ◽  
Pcr Assay ◽  
Specific Pcr ◽  
Specificity And Sensitivity ◽  
Pcr Products ◽  
Dna Fragment ◽  
Specific Pcr Assay ◽  
Dna Specificity ◽  
K 12

The gene (aroA) of Actinobacillus pleuropneumoniae, serotype 2, encoding 5-enolpyruvylshikimate-3-phosphate synthase was cloned by complementation of the aroA mutation in Escherichia coli K-12 strain AB2829, and the nucleotide sequence was determined. A pair of primers from the 5′ and 3′ termini were selected to be the basis for development of a specific PCR assay. A DNA fragment of 1,025 bp was amplified from lysed A. pleuropneumoniaeserotypes 1 to 12 of biovar 1 or from isolated DNA. No PCR products were detected when chromosomal DNAs from other genera were used as target DNAs; however, a 1,025-bp DNA fragment was amplified whenActinobacillus equuli chromosomal DNA was used as a target, which could be easily differentiated by its NAD independence. The PCR assay developed was very sensitive, with lower detection limits of 12 CFU with A. pleuropneumoniae cells and 0.8 pg with extracted DNA. Specificity and sensitivity make this PCR assay a useful method for the rapid identification and diagnosis of A. pleuropneumoniae infections.

Rapid identification of cervus antlers by species-specific PCR assay

2019 ◽  
Vol 34 (9) ◽  
pp. 1315-1319 ◽  
Author(s):  
Yaya Yang ◽  
Yang Zheng ◽  
Beibei Lu ◽  
Zhaoqun Jiao ◽  
Liqun Chen ◽  
...  
Keyword(s):  
Rapid Identification ◽  
Pcr Assay ◽  
Specific Pcr ◽  
Specific Pcr Assay ◽  
Species Specific

scholarly journals Sequence Analysis of the rfb Loci, Encoding Proteins Involved in the Biosynthesis of the Salmonella enterica O17 and O18 Antigens: Serogroup-Specific Identification by PCR

2006 ◽  
Vol 72 (12) ◽  
pp. 7949-7953 ◽  
Author(s):  
Collette Fitzgerald ◽  
Linda Gheesling ◽  
Marcus Collins ◽  
Patricia I. Fields
Keyword(s):  
Sequence Analysis ◽  
Gene Cluster ◽  
Salmonella Enterica ◽  
Rapid Identification ◽  
Specific Identification ◽  
O Antigen ◽  
Specific Pcr ◽  
Pcr Assays

ABSTRACT We report sequencing of the O antigen encoded by the rfb gene cluster of Salmonella enterica serotype Jangwani (O17) and Salmonella serotype Cerro (O18). We developed serogroup O17- and O18-specific PCR assays based on rfb gene targets and found them to be sensitive and specific for rapid identification of Salmonella serogroups O17 and O18.

Identification of Klebsiella oxytoca using a specific PCR assay targeting the polygalacturonase pehX gene

2003 ◽  
Vol 154 (8) ◽  
pp. 587-592 ◽  
Author(s):  
Gennadiy Kovtunovych ◽  
Tetyana Lytvynenko ◽  
Valentyna Negrutska ◽  
Olena Lar ◽  
Sylvain Brisse ◽  
...  
Keyword(s):  
Klebsiella Oxytoca ◽  
Pcr Assay ◽  
Specific Pcr ◽  
Specific Pcr Assay
Sign in / Sign up

Export Citation Format

Share Document