Identification and characterization of intervening sequences within 23S rRNA genes from more than 200 Campylobacter isolates from seven species including atypical campylobacters

<p>Abstract</p> <p>Background</p> <p>Identification and characterization of intervening sequences (IVSs) within 23S rRNA genes from <it>Campylobacter </it>organisms including atypical campylobacters were carried out using two PCR primer pairs, designed to generate helix 25 and 45 regions.</p> <p>Results</p> <p>Only <it>C. sputorum </it>biovar sputorum LMG7975 and fecalis LMG8531, LMG8534 and LMG6728 of a total of 204 <it>Campylobacter </it>isolates (n = 56 <it>C. jejuni</it>; n = 11 <it>C. coli</it>; n = 33 <it>C. fetus</it>; n = 43 <it>C. upsaliensis</it>; n = 30 <it>C. hyointestinalis</it>; n = 4 <it>C. sputorum </it>biovar sputorum; n = 5 <it>C. sputorum </it>biovar fecalis; n = 5 <it>C. sputorum </it>biovar paraureolyticus; n = 10 <it>C. concisus</it>; n = 7 <it>C. curvus</it>) were shown to carry IVSs in helix 25 region. <it>C. sputorum </it>biovar fecalis LMG8531 and LMG8534, interestingly, carried two different kinds of the 23S rRNA genes with and without the IVS, respectively. Consequently, in a total of 265 isolates of 269, including 65 <it>C. lari </it>isolates examined previously, the absence of IVSs was identified in the helix 25 region. In the helix 45 region, all the <it>C. hyointestinalis</it>, <it>C. sputorum </it>and <it>C. concisus </it>isolates were shown not to carry any IVSs. However, the 30 of 56 <it>C. jejuni </it>isolates (54%), 5 of 11 <it>C. coli </it>(45%), 25 of 33 <it>C. fetus </it>(76%), 30 of 43 <it>C. upsaliensis </it>(70%) and 6 of 7 <it>C. curvus </it>(90%) were shown to carry IVSs. In <it>C. jejuni </it>and <it>C. upsaliensis </it>isolates, two different kinds of the 23S rRNA genes were also identified to occur with and without IVSs in the helix 45 region, respectively.</p> <p>Conclusions</p> <p>Secondary structure models were also constructed with all the IVSs identified in the present study. In the purified RNA fractions from the isolates which carried the 16S or 23S rRNA genes with the IVSs, no 16S or 23S rRNA was evident, respectively.</p

JSPS-9 Microbiologial Quality of Chicken Carcasses in Bogor Indonesia Based on Campylobater sp. and Salmonella sp. Counts

Unhygienic handling chicken carcasses during slaughtering until selling to costumers can lead to contamination by pathogenic bacteria such as Campylobacter sp., and Salmonella sp. entering human’s body can cause foodborne diseaseThe aims of this study were to detect contamination and enumuration of Campylobacter sp, and Salmonella sp. in chicken carcasses from poultry slauhterhouses and markets in Bogor Indonesia

Detection of a Group II Intron without an Open Reading Frame in the Alpha-Toxin Gene of Clostridium perfringens Isolated from a Broiler Chicken

A DNA insertion of 834 bp, designated CPF-G2Im, was identified within the alpha toxin gene (cpa) of Clostridium perfringens strain CPBC16ML, isolated from a broiler chicken. Sequence analysis of CPF-G2Im indicated that it was integrated 340 nucleotides downstream of the start codon of cpa. However, the insertion did not abolish the phospholipase C and hemolytic activities of CPBC16ML. To investigate the expression of its alpha toxin, the intact copy of cpa was cloned into an expression vector and transformed into Escherichia coli M15 cells. Immunoblotting analysis showed that the protein expressed from the transformant as well as in the culture supernatant of C. perfringens strain CPBC16ML had the expected molecular weight detected in reference strains of C. perfringens. Northern hybridization and reverse transcriptase PCR (RT-PCR) analysis revealed that the entire CPF-G2Im insertion was completely spliced from the cpa precursor mRNA transcripts. The sequence of the insertion fragment has 95% and 97% identity to two noncoding regions corresponding to sequences that flank a predicted group II RT gene present in the pCPF4969 plasmid of C. perfringens. However, an RT was not encoded by the CPF-G2Im fragment. Based on the secondary structure prediction analysis, CPF-G2Im revealed typical features of group II introns. The present study shows that CPF-G2Im is capable of splicing in both C. perfringens and E. coli. To our knowledge, this is the first report that a group II intron without an open reading frame (ORF) is located in the cpa ORF of C. perfringens