scholarly journals Detection of Mycoplasma hyopneumoniae in nose swabs from pigs by in vitro amplification of the 16S rRNA gene.

1995 ◽  
Vol 33 (4) ◽  
pp. 893-897 ◽  
Author(s):  
J G Mattsson ◽  
K Bergström ◽  
P Wallgren ◽  
K E Johansson
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Mycoplasma Hyopneumoniae ◽  
Rrna Gene ◽  
The 16S Rrna Gene

scholarly journals Quantification of Expression of Staphylococcus epidermidis Housekeeping Genes with Taqman Quantitative PCR during In Vitro Growth and under Different Conditions

2001 ◽  
Vol 183 (24) ◽  
pp. 7094-7101 ◽  
Author(s):  
S. J. Vandecasteele ◽  
W. E. Peetermans ◽  
R. Merckx ◽  
J. Van Eldere
Keyword(s):  
Gene Expression ◽  
Heat Shock ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Quantitative Pcr ◽  
Housekeeping Genes ◽  
Rrna Gene ◽  
In Vitro Growth ◽  
The 16S Rrna Gene

ABSTRACT The aims of the present study were (i) to develop and test a sensitive and reproducible method for the study of gene expression in staphylococci and (ii) to study the expression of five housekeeping genes which are involved in nucleic acid metabolism (gmk, guanylate kinase; the dihydrofolate reductase [DHFR] gene), glucose metabolism (tpi, triosephosphate isomerase), and protein metabolism (the 16S rRNA gene;hsp-60, heat-shock protein 60) during in vitro exponential and stationary growth. A modified method for instant mRNA isolation was combined with gene quantification via Taqman real-time quantitative PCR. The detection limit of our method was 10 copies of RNA. The average intersample variability was 16%. A 10-fold increase in the expression of the hsp-60 gene was induced by exposure to a 10°C heat shock (37 to 47°C) for 10 min. During in vitro growth, the expression of all five housekeeping genes showed rapid up-regulation after inoculation of the bacteria in brain heart infusion medum and started to decline during the mid-exponential-growth phase. Maximal gene expression was 110- to 300-fold higher than gene expression during stationary phase. This indicates that housekeeping metabolism is a very dynamic process that is extremely capable of adapting to different growth conditions. Expression of the 16S rRNA gene decreases significantly earlier than that of other housekeeping genes. This confirms earlier findings forEscherichia coli that a decline in bacterial ribosomal content (measured by 16S rRNA gene expression) precedes the decline in protein synthesis (measured by mRNA expression).

Identification of 16S rRNA mutations in Mycoplasma genitalium potentially associated with tetracycline resistance in vivo but not selected in vitro in M. genitalium and Chlamydia trachomatis

2021 ◽  
Author(s):  
Chloé Le Roy ◽  
Arabella Touati ◽  
Carla Balcon ◽  
Justine Garraud ◽  
Jean-Michel Molina ◽  
...  
Keyword(s):  
Chlamydia Trachomatis ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Tetracycline Resistance ◽  
Mycoplasma Genitalium ◽  
Rrna Gene ◽  
Resistant Mutants ◽  
The 16S Rrna Gene

Abstract Objectives Tetracyclines are widely used for the treatment of bacterial sexually transmitted infections (STIs) and recently have been used successfully for post-exposure prophylaxis of STIs in MSM. We investigated the in vitro and in vivo development of tetracycline resistance in Chlamydia trachomatis and Mycoplasma genitalium and evaluated 16S rRNA mutations associated with acquired resistance in other bacteria. Methods In vitro selection of resistant mutants of reference strains of C. trachomatis and M. genitalium was undertaken by serial passage in medium containing subinhibitory concentrations of tetracycline or doxycycline, respectively. The 16S rRNA gene of the two microorganisms was amplified and sequenced at different passages, as were those of 43 C. trachomatis- and 106 M. genitalium-positive specimens collected in France from 2013 to 2019. Results No tetracycline- or doxycycline-resistant strains of C. trachomatis and M. genitalium, respectively, were obtained after 30 serial passages. The tetracycline and doxycycline MICs were unchanged and analysis of the 16S rRNA gene, the molecular target of tetracyclines, of C. trachomatis and M. genitalium revealed no mutation. No mutation in the 16S rRNA gene was detected in C. trachomatis-positive specimens. However, six M. genitalium-positive specimens harboured a mutation potentially associated with tetracycline resistance without known prior tetracycline treatment for patients. Conclusions Tetracyclines did not select in vitro-resistant mutants of C. trachomatis or M. genitalium. However, 16S rRNA mutations either responsible for or associated with tetracycline resistance in other bacteria, including mycoplasma species, were identified in several M. genitalium-positive specimens.

A spiroplasma associated with tremor disease in the Chinese mitten crab (Eriocheir sinensis)

Microbiology ◽  
2004 ◽  
Vol 150 (9) ◽  
pp. 3035-3040 ◽  
Author(s):  
Wen Wang ◽  
Bohai Wen ◽  
Gail E. Gasparich ◽  
Ningning Zhu ◽  
Liwen Rong ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Light And Electron Microscopy ◽  
Eriocheir Sinensis ◽  
Rrna Gene ◽  
Chinese Mitten Crab ◽  
Mitten Crab ◽  
The 16S Rrna Gene

An epidemic of tremor disease has been a serious problem in Chinese mitten crabs, Eriocheir sinensis, in China in recent years. The disease-causing agent was previously considered to be a rickettsia-like organism. Here, analysis of the 16S rRNA gene sequence, light and electron microscopy and cultivation in vitro were used to identify the agent. Sequence analysis of the 16S rRNA gene found it to have 98 % identity with that of Spiroplasma mirum. The agent was able to be passed through membrane filters with pores 220 nm in diameter and could be cultivated by inoculating the yolk sac of embryonated chicken eggs and M1D medium. Rotary motion and flexional movement were seen by light microscopy, and electron microscopy showed that the organism had a helical morphology and lacked a cell wall. The organism produced small colonies with a diameter of 40–50 μm after 17–25 days of incubation on solid M1D medium. The agent was found in blood cells, muscles, nerves and connective tissues of crabs inoculated with a filtrate of yolk sacs or with cultures grown in M1D medium, and it was similar in structure to those grown in eggs and cultivation broth. Disease was reproduced by experimental infection with the cultivated organisms. This study has demonstrated that the causative agent of tremor disease in the Chinese mitten crab is a member of the genus Spiroplasma. This is believed to be the first time a spiroplasma has been found in a crustacean. These findings are not only significant for studies on pathogenic spiroplasmas, but also have implications for studies of freshwater ecology.

scholarly journals Phyllobacterium loti sp. nov. isolated from nodules of Lotus corniculatus

2014 ◽  
Vol 64 (Pt_3) ◽  
pp. 781-786 ◽  
Author(s):  
Maximo Sánchez ◽  
Martha-Helena Ramírez-Bahena ◽  
Alvaro Peix ◽  
María J. Lorite ◽  
Juan Sanjuán ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Sequence Similarity ◽  
Carbon Sources ◽  
Lotus Corniculatus ◽  
Culture Conditions ◽  
Rrna Gene ◽  
Content Type ◽  
Link Type ◽  
The 16S Rrna Gene

Strain S658T was isolated from a Lotus corniculatus nodule in a soil sample obtained in Uruguay. Phylogenetic analysis of the 16S rRNA gene and atpD gene showed that this strain clustered within the genus Phyllobacterium . The closest related species was, in both cases, Phyllobacterium trifolii PETP02T with 99.8 % sequence similarity in the 16S rRNA gene and 96.1 % in the atpD gene. The 16S rRNA gene contains an insert at the beginning of the sequence that has no similarities with other inserts present in the same gene in described rhizobial species. Ubiquinone Q-10 was the only quinone detected. Strain S658T differed from its closest relatives through its growth in diverse culture conditions and in the assimilation of several carbon sources. It was not able to reproduce nodules in Lotus corniculatus. The results of DNA–DNA hybridization, phenotypic tests and fatty acid analyses confirmed that this strain should be classified as a representative of a novel species of the genus Phyllobacterium , for which the name Phyllobacterium loti sp. nov. is proposed. The type strain is S658T( = LMG 27289T = CECT 8230T).

scholarly journals Diagnosis of Fulminant Pneumonia Caused by Legionella pneumophila Serogroup 8 with the Sequence Analysis of the 16S rRNA Gene

2011 ◽  
Vol 225 (1) ◽  
pp. 65-69 ◽  
Author(s):  
Toshinori Kawanami ◽  
Kazuhiro Yatera ◽  
Kazumasa Fukuda ◽  
Kei Yamasaki ◽  
Masamizu Kunimoto ◽  
...  
Keyword(s):  
Sequence Analysis ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Legionella Pneumophila ◽  
Rrna Gene ◽  
The 16S Rrna Gene

scholarly journals The Western Progression of Lyme Disease: Infectious and NonclonalBorrelia burgdorferi Sensu LatoPopulations in Grand Forks County, North Dakota

2014 ◽  
Vol 81 (1) ◽  
pp. 48-58 ◽  
Author(s):  
Brandee L. Stone ◽  
Nathan M. Russart ◽  
Robert A. Gaultney ◽  
Angela M. Floden ◽  
Jefferson A. Vaughan ◽  
...  
Keyword(s):  
Lyme Disease ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
North Dakota ◽  
Intergenic Spacer ◽  
Rrna Gene ◽  
Content Type ◽  
Intergenic Spacer Region ◽  
Grand Forks ◽  
The 16S Rrna Gene

ABSTRACTScant attention has been paid to Lyme disease,Borrelia burgdorferi,Ixodes scapularis, or reservoirs in eastern North Dakota despite the fact that it borders high-risk counties in Minnesota. Recent reports ofB. burgdorferiandI. scapularisin North Dakota, however, prompted a more detailed examination. Spirochetes cultured from the hearts of five rodents trapped in Grand Forks County, ND, were identified asB. burgdorferi sensu latothrough sequence analyses of the 16S rRNA gene, the 16S rRNA gene-ileTintergenic spacer region,flaB,ospA,ospC, andp66. OspC typing revealed the presence of groups A, B, E, F, L, and I. Two rodents were concurrently carrying multiple OspC types. Multilocus sequence typing suggested the eastern North Dakota strains are most closely related to those found in neighboring regions of the upper Midwest and Canada. BALB/c mice were infected withB. burgdorferiisolate M3 (OspC group B) by needle inoculation or tick bite. Tibiotarsal joints and ear pinnae were culture positive, andB. burgdorferiM3 was detected by quantitative PCR (qPCR) in the tibiotarsal joints, hearts, and ear pinnae of infected mice. Uninfected larvalI. scapularisticks were able to acquireB. burgdorferiM3 from infected mice; M3 was maintained inI. scapularisduring the molt from larva to nymph; and further, M3 was transmitted from infectedI. scapularisnymphs to naive mice, as evidenced by cultures and qPCR analyses. These results demonstrate that isolate M3 is capable of disseminated infection by both artificial and natural routes of infection. This study confirms the presence of unique (nonclonal) and infectiousB. burgdorferipopulations in eastern North Dakota.

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