Detection of DNA sequence polymorphisms in carcinogen metabolism genes by polymerase chain reaction

1991 ◽  
Vol 18 (4) ◽  
pp. 245-248 ◽  
Author(s):  
Douglas A. Bell
The Prostate ◽  
1993 ◽  
Vol 22 (1) ◽  
pp. 11-22 ◽  
Author(s):  
Zoran Culig ◽  
Helmut Klocker ◽  
Johannes Eberle ◽  
Felizia Kaspar ◽  
Alfred Hobisch ◽  
...  

2002 ◽  
Vol 65 (1) ◽  
pp. 5-11 ◽  
Author(s):  
TAKAHISA MIYAMOTO ◽  
NATSUKO ICHIOKA ◽  
CHIE SASAKI ◽  
HIROSHI KOBAYASHI ◽  
KEN-ICHI HONJOH ◽  
...  

The DNA band patterns generated by polymerase chain reaction (PCR) using the du2 primer and template DNAs from various strains of Escherichia coli and non–E. coli bacteria were compared. Among three to five prominent bands produced, the three bands at about 1.8, 2.7, and 5.0 kb were detected in all of the E. coli O157 strains tested. Some nonpathogenic E. coli and all pathogenic E. coli except E. coli O157 showed bands at 1.8 and 5.0 kb. It seems that the band at 2.7 kb is specific to E. coli O157. Sequence analysis of the 2.7-kb PCR product revealed the presence of a DNA sequence specific to E. coli O157:H− and E. coli O157:H7. Since the DNA sequence from base 15 to base 1008 of the PCR product seems to be specific to E. coli O157, a PCR assay was carried out with various bacterial genomic DNAs and O157-FHC1 and O157-FHC2 primers that amplified the region between base 23 and base 994 of the 2.7-kb PCR product. A single band at 970 bp was clearly detected in all of the strains of E. coli O157:H− and E. coli O157:H7 tested. However, no band was amplified from template DNAs from other bacteria, including both nonpathogenic and pathogenic E. coli except E. coli O157. All raw meats inoculated with E. coli O157:H7 at 3 × 100 to 3.5 × 102 CFU/25 g were positive both for our PCR assay after cultivation in mEC-N broth at 42°C for 18 h and for the conventional cultural method.


1991 ◽  
Vol 48 (1) ◽  
pp. 48-52 ◽  
Author(s):  
Steven M. Carr ◽  
H. Dawn Marshall

We determined the DNA sequence of a portion of the mitochondrial cytochrome b gene for 55 Atlantic cod (Gadus morhua) from Norway and from 10 locations within the Northern Cod complex and adjacent stocks off Newfoundland. DNA was prepared for sequencing by the polymerase chain reaction (PCR). Eleven variable nucleotide positions within a 298 base region defined 12 genotypes. Genotype proportions differed significantly between Newfoundland and Norwegian populations: the majority genotype among Newfoundland populations was present in a minority of Norwegian cod. Newfoundland cod showed less genotypic diversity than those from the eastern Atlantic: nine genotypes were found among all 10 Newfoundland populations, as compared with seven genotypes within the single Norwegian population. An exception was an overwintering, inshore Newfoundland population that showed four genotypes among five fish. As in other vertebrates, third position synonymous transitions predominate over other types of nucleotide changes. However, two amino acid replacement substitutions occur among cod, and the ratio of purine transitions to pyrimidine transitions is significantly higher than in other species. The existence of DNA sequence polymorphism permits the various hypotheses of the distribution and differentiation of Newfoundland cod stocks to be tested, and points to the utility of PCR technology in fishery genetics.


2007 ◽  
Vol 19 (5) ◽  
pp. 532-534 ◽  
Author(s):  
John A. Angelos ◽  
Louise M. Ball

Moraxella oris was historically the only coccoid Moraxella identified in cultures of ocular fluid from cattle with infectious bovine keratoconjunctivitis (IBK) and could be morphologically and biochemically differentiated from Moraxella bovis. Moraxella bovoculi sp. nov. is a recently characterized Moraxella isolated from ulcerated eyes of calves with IBK in northern California in 2002. Like Moraxella ovis, M. bovoculi sp. nov. is a gram-negative coccus/diplococcus. All 18 original isolates of M. bovoculi sp. nov. possessed phenylalanine deaminase (PADase) activity and could therefore be differentiated from M. ovis and M. bovis. During the characterization of 44 additional isolates of hemolytic gram-negative cocci that were cultured from ulcerated eyes of IBK-affected calves, 2 PADase-negative isolates were identified that could not be differentiated biochemically from M. ovis; however, the DNA sequence of the 16S-23S intergenic spacer region (ISR) of the isolates matched the 16S-23S ISR DNA sequence of M. bovoculi sp. nov. To facilitate the identification of PADase-negative moraxellae, a polymerase chain reaction (PCR) coupled with restriction enzyme digestion analysis of amplified DNA was developed. Amplification of the 16S-23S ISR followed by AfaI digestion of amplified DNA could differentiate M. bovoculi sp. nov. from M. ovis and other moraxellae. The DNA sequence analysis of the amplified 16S-23S ISR from the 42 PADase-positive isolates of hemolytic gram-negative cocci indicated that all were M. bovoculi sp. nov. and all possessed an AfaI site. A PCR coupled with restriction analysis of amplified DNA can aid in identifying M. bovoculi sp. nov.


Sign in / Sign up

Export Citation Format

Share Document