scholarly journals Comparison of 16S rDNA and 16S/23S Intergenic Region Sequences Among Citrus Greening Organisms in Asia

Plant Disease ◽  
2000 ◽  
Vol 84 (1) ◽  
pp. 15-18 ◽  
Author(s):  
Siti Subandiyah ◽  
Toru Iwanami ◽  
Shinji Tsuyumu ◽  
Hiroyuki Ieki
Keyword(s):  
16S Rdna ◽  
Ribosomal Rna ◽  
Intergenic Region ◽  
The Philippines ◽  
Citrus Greening ◽  
Chain Reaction ◽  
African Strain ◽  
16S Ribosomal Rna Gene ◽  
Polymerase Chain ◽  
India And China

Polymerase chain reaction was used to amplify and sequence the 16S ribosomal RNA gene (rDNA) and 16S/23S intergenic region of several isolates of citrus greening organism (GO) from Japan, the Philippines, Indonesia, and Thailand. The sequences of 16S rDNA were identical among all the isolates studied, very similar to the published sequences of Thai (99.4 to 100% identity), Nepalese (100% identity), and Indian (98.8% identity) strains, and less similar to an African strain (97.5% identity). The sequences of the intergenic region between 16S and 23S rDNA were also identical among the isolates examined as well as the reported Nepalese and Thai isolates. They were close to the sequences of reported strains of India and China (99.2%) and apart from those of the African strain (85.5%). These results suggested that some isolates of GO from Japan, the Philippines, Indonesia, Thailand, and Nepal constitute one strain, which is similar to Indian and Chinese strains and distinct from the African strain.

Cultural and molecular characterization of photobionts of Peltigera Membranacea

1997 ◽  
Vol 29 (6) ◽  
pp. 571-586 ◽  
Author(s):  
V.P.W. Mioa ◽  
A. Rabenau ◽  
A. Lee
Keyword(s):  
16S Rdna ◽  
Ribosomal Rna ◽  
Molecular Study ◽  
16S Ribosomal Rna ◽  
Chain Reaction ◽  
Ribosomal Rna Gene ◽  
Pcr Product ◽  
16S Ribosomal Rna Gene ◽  
Polymerase Chain

AbstractA molecular study was undertaken to clarify the identity of the photobiont in colourmorphs of the lichen, Peltigera membranacea. Two strains of cyanobacteria, identified as Nosroc sp. by morphology, were cultivated from each of two lichen specimens. Prokaryotic (16S) ribosomal RNA gene fragments were amplified by the polymerase chain reaction (PCR) from DNA extracted from the isolated strains and the lichens, and sequenced directly. Sequences were 98 1% identical between lichen specimens, TDI#AR94 and TDI#AR95, and highly similar to sequences published, or generated in this study from a type culture, for Nostoc. The 16S ribosomal RNA gene sequences (‘ 16S rDNA’) of all four lichen-derived cyanobacteria appeared the same, even though the lichen specimens from which they originated had different sequences. The 16S rDXA from strains 9A and 9B were different from that of specimen TDI#AR94, the thallus from which they were isolated, and instead were the same as that of strains 10A and 10B, and their source, specimen TDI#AR95. When primers selective for the strain 9A sequence were used, however, a small amount of PCR product corresponding to the 16S rDNA of strain 9A was obtained from lichen TDI#AR94. The results confirm that the photobionts of P. membranacea belong to Nostoc, and suggest that genetic differences in the photobiont may be a factor in the occurrence of colourmorphs among cyanolichens.

scholarly journals Specific Vaginal Bacteria Are Associated With an Increased Risk of Trichomonas vaginalis Acquisition in Women

2019 ◽  
Vol 220 (9) ◽  
pp. 1503-1510 ◽  
Author(s):  
Olamide D Jarrett ◽  
Sujatha Srinivasan ◽  
Barbra A Richardson ◽  
Tina Fiedler ◽  
Jacqueline M Wallis ◽  
...  
Keyword(s):  
Ribosomal Rna ◽  
Trichomonas Vaginalis ◽  
Bacterial Species ◽  
Polymerase Chain Reaction Analysis ◽  
Vaginal Microbiota ◽  
Menstrual Phase ◽  
Chain Reaction ◽  
Increased Risk ◽  
16S Ribosomal Rna Gene ◽  
Polymerase Chain

Abstract Background While bacterial vaginosis has been associated with an increased risk of Trichomonas vaginalis (TV) acquisition, it is unknown whether other characteristics of the vaginal microbiota, including the presence of key bacterial species, influence a woman’s risk of TV acquisition. Methods The vaginal microbiota before 25 unique episodes of TV infection involving 18 women was compared to that of 50 controls who remained uninfected. TV was detected by transcription-mediated amplification. Vaginal microbiota were quantified using broad-range polymerase chain reaction analysis and taxon-specific quantitative PCR of the 16S ribosomal RNA gene. Results TV acquisition was significantly associated with the presence of Prevotella amnii (risk ratio [RR], 2.21; 95% confidence interval [CI], 1.12–4.38; P = .02) and Sneathia sanguinegens (RR, 2.58; 95% CI, 1.00–6.62; P = .049). When adjusted for menstrual phase, the association between P. amnii and TV acquisition remained similar (adjusted RR, 2.11; 95% CI, 1.03–4.33; P = .04), but the association between S. sanguinegens and TV acquisition was attenuated (adjusted RR, 2.31; 95% CI, .86–6.23; P = .10). Conclusions Key vaginal bacterial species may contribute to the susceptibility to TV acquisition. Understanding how these bacterial species increase a woman’s risk of TV acquisition could help to guide the development of novel strategies to reduce women’s risk of TV infection.

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