Objective: To evaluate multidrug resistant loop-mediated isothermal amplification (MDR-LAMP) assay for the early diagnosis of multidrug-resistant tuberculosis and to compare the mutation patterns associated with the Methods: MDR-LAMP assay was evaluated using 100 Results: The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MDR-LAMP were 85.5%, 93.6%, 96.7%, and 74.4% for the detection of resistance to isoniazid and rifampicin, respectively, and 80.5%, 92.3%, 98.6%, and 41.4% for the detection of Conclusion MDR-LAMP is a rapid and accessible assay for the laboratory identification of rifampicin and isoniazid resistance of
Antitubercular Agents ; Bacterial Proteins/genetics* ; Catalase/genetics* ; DNA, Bacterial/analysis* ; DNA-Directed RNA Polymerases/genetics* ; Drug Resistance, Multiple, Bacterial/genetics* ; Isoniazid ; Molecular Diagnostic Techniques/methods* ; Mutation ; Mycobacterium tuberculosis/isolation & purification* ; Nucleic Acid Amplification Techniques/methods* ; Oxidoreductases/genetics* ; Phenotype ; Rifampin ; Whole Genome Sequencing

The purpose of this study is to provide a simple and reliable genetic typing approach for molecular drug susceptibility test of Mycobacterium tuberculosis, through the developing of fluorescence molecular marker of rifampicin resistance gene rpoB. Eleven fluorescent molecular markers of the rpoB gene were established by using the sequence difference between the amino acid positions 531, 526, 516, 511 and 513 of rpoB gene of rifampicin-resistant strains and the alleles of rifampicin-sensitive strains, combined with the PARMS technique (Penta-primer amplification refractory mutation system). We used 104 clinical isolates of Mycobacterium tuberculosis to validate this marker and it was verified by sequencing as 100% correct. These samples were also tested with proportional drug sensitivity test. The coincidence rate was 94.23%. The molecular markers had high reliability for genotyping of rpoB gene. It can also detect low-concentration drug-resistant samples (511/533 unit point mutations) whose phenotypic susceptibility cannot be detected. The eleven sets of fluorescent molecular markers could cover 92%-96% of rpoB gene mutation types of rifampicin-resistant strains, and provide new idea for rapid detection of rifampin-resistant Mycobacterium tuberculosis.
Bacterial Proteins/genetics* ; DNA-Directed RNA Polymerases/genetics* ; Drug Resistance, Bacterial/genetics* ; Microbial Sensitivity Tests ; Mutation ; Mycobacterium tuberculosis/genetics* ; Reproducibility of Results ; Rifampin/pharmacology* ; Technology

The low expression rate of exogenous genes in cyanobacteria is one of the bottlenecks of cyanobacteria genetic engineering. The T7 RNA polymerase expression system has achieved the efficient expression of exogenous genes in Escherichia coli. Cyanobacteria and E. coli are both Gram-negative bacteria with high genetic homology. The construction of T7 RNA polymerase expression system in cyanobacteria may improve the expression of foreign genes. In order to construct the T7 RNA polymerase expression system in Anabaena sp. PCC 7120, methods such as overlapping extension PCR and digestion-ligation technique were used to construct a site-specific integration vector pEASY-T1-F1-TacT7RNAPCmR-F2 and a shuttle expression vector pRL-T7-hG-CSF. The site-specific integration vector is capable of expressing T7 RNA polymerase, and the shuttle expression vector expresses hG-CSF driven by the T7 promoter. Then we introduced the site-specific integration vector into the wild type cyanobacteria by electroporation and transferred the shuttle expression vector into the site-integrated transgenic cyanobacteria by triparental conjugative transfer. In the end, we identified the presence of foreign genes in cyanobacteria by PCR, tested the transcription level of foreign genes in cyanobacteria by RT-PCR, and detected the protein expression of foreign genes in cyanobacteria by Western blotting. The two vectors were successfully constructed, the T7 RNA polymerase gene and hG-CSF gene were transferred into cyanobacteria well, and both genes were also expressed in cyanobacteria. In summary, the T7 RNA polymerase expression system was successfully constructed in cyanobacteria, and the expression rate of hG-CSF gene was doubled than the traditional cyanobacteria expression systems. This expression system will provide a better tool for the application of cyanobacteria genetic engineering and will promote the development of cyanobacteria as a chassis cell in the fields of synthetic biology in the future.
Anabaena/genetics* ; Cloning, Molecular ; DNA-Directed RNA Polymerases ; Escherichia coli/genetics* ; Gene Expression ; Mercury ; Plasmids ; Viral Proteins

Treacher Collins syndrome is a congenital craniofacial malformation with autosomal dominant inheritance as the main genetic pattern. In this condition, the biosynthesis of ribosomes in neural crest cells and neuroepithelial cells is blocked and the number of neural crest cells that migrate to the craniofacial region decreases, causing first and second branchial arch dysplasia. Definite causative genes include treacle ribosome biogenesis factor 1 (tcof1), RNA polymerase Ⅰ and Ⅲ subunit C (polr1c), and RNA polymerase Ⅰ and Ⅲ subunit D (polr1d). This paper provides a review of research of three major patho-genic genes, pathogenesis, phenotypic research, prevention, and treatment of the syndrome.
DNA-Directed RNA Polymerases ; genetics ; Humans ; Mandibulofacial Dysostosis ; genetics ; Neural Crest ; Nuclear Proteins ; Phosphoproteins

We evaluate the performance of Xpert MTB/RIF for the diagnosis of extrapulmonary tuberculosis (EPTB) in China. The performance of Xpert was evaluated compared to the composite reference standard (CRS), drug susceptibility testing (DST), and imaging examination. The overall sensitivity and specificity of Xpert were 64.1% (195/304) and 100% (24/24), respectively, using CRS as the gold standard. The sensitivity was significantly higher than that of culture for pus (P<0.05). The proportion of EPTB-positive cases diagnosed by imaging was two times more than that diagnosed using Xpert; however, 6 out of 19 cases may have been overdiagnosed by imaging. Compared to phenotypic DST, the sensitivity and specificity of Xpert were 80% (12/15) and 100% (75/75), respectively. Considering its high sensitivity and specificity, Xpert MTB/RIF may be used as a rapid initial test for EPTB diagnosis, and may also support a quicker decision on the treatment regimen. The combination of imaging and Xpert testing could provide high efficiency and accurate diagnosis of suspected EPTB.
Bacterial Proteins ; genetics ; metabolism ; China ; DNA-Directed RNA Polymerases ; genetics ; metabolism ; Diagnostic Tests, Routine ; instrumentation ; methods ; Drug Resistance, Bacterial ; Humans ; Microbial Sensitivity Tests ; Mycobacterium tuberculosis ; drug effects ; genetics ; isolation & purification ; metabolism ; Retrospective Studies ; Rifampin ; pharmacology ; Sensitivity and Specificity ; Sputum ; Tuberculosis ; Tuberculosis, Pulmonary ; diagnosis ; microbiology

Mammals have 3 pairs of major salivary glands i.e., the parotid, submandibular, and sublingual glands. Saliva secretion of these glands is modulated by taste perception. Salivary glands are composed mainly of acinar and ductal cells. Primary saliva is secreted by acinar cells and modified during ductal flow. Recently, of the murine 35 bitter taste receptors, Tas2r108 was expressed at highest levels in the submandibular gland by qPCR. Further, Tas2r108-transfected cells respond to a range of bitter compounds, such as denatonium, quinine, colchicine, diphenidol, caffeine and dapson. The objective of the present study was to characterize the expression of Tas2r108 mRNA in acinar and/or ductal cells of the submandibular gland using in situ hybridization (ISH). Male 42-60 days old DBA2 mice were used in the study. Messenger RNAs were extracted from the submandibular gland for generating digoxigenin (DIG) labeled-cRNA probes. These probes were transcribed in anti-sense and sense orientation using T7 RNA polymerase. Dot blot hybridization was performed using DIG labeled-cRNA probes, in order to estimate integrity and optimal diluting concentration of these probes. Subsequently, ISH was performed on murine submandibular gland to detect Tas2r108 mRNA. Dot blot hybridization data demonstrated that Tas2r108 DIG labeled-cRNA anti-sense probes specifically detected Tas2r108 cDNA. ISH results showed that the anti-sense probes labeled acinar and ductal cells in the submandibular gland, whereas no staining was visible in sense controls. Interestingly, the Tas2r108 expression levels were higher in acinar than ductal cells. These results suggested that Tas2r108 might be more associated with primary saliva secretion than with ductal modification of saliva composition.
Acinar Cells ; Animals ; Antisense Elements (Genetics) ; Caffeine ; Colchicine ; Digoxigenin ; DNA, Complementary ; DNA-Directed RNA Polymerases ; Humans ; In Situ Hybridization* ; Male ; Mammals ; Mice ; Quinine ; RNA, Messenger ; Saliva ; Salivary Glands ; Sublingual Gland ; Submandibular Gland* ; Taste Perception

Treacher Collins syndrome (TCS, OMIM 154500), also known as Franceschetti-Klein syndrome, is a rare disorder that affects the first and second branchial arches. The estimated incidence is 1/50 000 live births. Mutations in TCOF1 (78%-93%) and POLR1C or POLR1D (8%) cause the disease. Most of TCS cases are inherited in a dominant pattern, while a small proportion are inherited in a recessive pattern. TCS has a variable phenotype with typical clinical characteristics including downward-slant of palpebral fissure, malar hypoplasia, mandibular hypoplasia and microtia. TCS management is a multidisciplinary affair, as interventions range from reconstructive to psychosocial. For hearing rehabilitation, TCS patients may have the choices of BAHA, ponto, vibrant soundbridge or bonebridge implantation. In this review, we summarize the TCS clinical malformations, diagnosis, genetics, management and auditory rehabilitation.
DNA-Directed RNA Polymerases ; genetics ; Facial Bones ; abnormalities ; Humans ; Mandibulofacial Dysostosis ; diagnosis ; genetics ; rehabilitation ; Mutation ; Nuclear Proteins ; genetics ; Phosphoproteins ; genetics

In this study, we constructed the plasmid of Sendai virus (SeV) BB1 strain minigenome with Gaussia luciferase (Gluc) as reporter and compared the rescue efficiency of SeV minigenome mediated by T7 promoter with that by CMV promoter. Firstly, the sequence was designed and synthesized which contained hammerhead ribozyme, sequence composed of the trailer, untranslated region of L gene, untranslated region of N gene, and the leader from SeV, and mutant hepatitis delta virus ribozyme sequence. Then, the synthesized sequence was inserted into pVAX1 containing CMV and T7 promoters and the general vector for SeV minigenome pVAX-miniSeV was obtained. Furthermore, pVAX-miniSeV-Gluc (+) and pVAX-miniSeV-Gluc(-) were obtained by inserting Gluc gene into pVAX-miniSeV. From the supernatant of BHK-21 cell transfected with pVAX-miniSeV-Gluc(+), high level of Gluc expression was detection indicating the normal transcription function of CMV promoter. pVAX-SeV-miniGluc(-) and plasmids expressing N,P and L protein of SeV were co-transfected into BST T7/5 cell which derived from BHK-21 and expressed T7 RNA polymerase stably. And high expression of Gluc was found, which indicated that SeV minigenome was efficiently rescued. However, we failed to repeat the result on BHK-21 cell, implying that T7 promoter and CMV promoter may have different effects on the rescue efficiency of SeV minigenome. Therefore, we further constructed SeV minigenome vectors pT7-miniSeV-Gluc (-) and pCMV-miniSeV-Gluc(-) with single promoter of T7 or CMV. Then, these vectors were transfected into BSR T7/ 5 cells respectively accompanied with the N, P, and L protein expression vectors. The result demonstrated that high expression of Gluc was found in the group of pT7-miniSeV-Gluc(-), which failed in the group of pCMV-miniSeV-Gluc(-). It indicated that T7 promoter significantly increased the rescue efficiency of SeV minigenome. We successfully constructed a SeV minigenome vector with secreted luciferase gene as report er and proved T7 promoter can enhance the rescue efficiency of SeV minigenome, which provides basis for construction of infectious clone containing SeV full-length genome.
Animals ; Cell Line ; Cricetinae ; Cytomegalovirus ; genetics ; DNA-Directed RNA Polymerases ; genetics ; Genome, Viral ; Humans ; Promoter Regions, Genetic ; Respirovirus Infections ; virology ; Sendai virus ; genetics ; physiology ; Viral Proteins ; genetics ; metabolism

OBJECTIVETo study the characteristics of drug-resistant genetic mutation of rpoB in multiple drugs resistant bacillus tuberculosis (MDR-TB) among patients of pneumoconiosis complicated with pulmonary tuberculosis.

METHODSA total of 114 clinical isolated strains of Mycobacterium tuberculosis were collected, MDR-TB were identified by conventional antimicrobial susceptibility test (AST). Their genomes DNA were extracted, the target genes were amplified by PCR, and the hot regions in the rpoB gene were analyzed by automated DNA sequenator.

RESULTSThe results by AST showed that there were 31 strains of MDR-TB in the 114 clinical isolated strains, the rate of drug resistance was 27.19% (31/114). No mutation of rpoB was identified in 10 rifampicin-sensitive strains that randomly chosen, while conformation changes were found in MDR-TB strains, and the mutation rate of rpoB was 93.55% (29/31) in resistant strains, mainly concentrated in codon 531 (45.16%, 14/31) and 526 (29.03%, 9/31), happened base substitutions, including 27 unit point mutation and 2 two point mutation.

CONCLUSIONSThe substitution of highly conserved amino acids encoded by rpoB gene results in the molecular mechanism responsible for RFP resistance in MDR-TB among patients of pneumoconiosis complicated with pulmonary tuberculosis. It also proves that rpoB gene is diversiform.

Adult ; Aged ; Bacterial Proteins ; genetics ; DNA-Directed RNA Polymerases ; Drug Resistance, Multiple, Bacterial ; genetics ; Genes, Bacterial ; Humans ; Male ; Microbial Sensitivity Tests ; Middle Aged ; Mining ; Mutation Rate ; Mycobacterium tuberculosis ; drug effects ; genetics ; isolation & purification ; Pneumoconiosis ; microbiology ; Sequence Analysis ; Tuberculosis, Pulmonary ; microbiology

OBJECTIVETo evaluate the clinical performance of a probe melting analysis (PMA)-based real-time PCR detection kit in rapid detection of rifampin-resistant mutations in Mycobacterium tuberculosis (MTB).

METHODSThe specificity of the assay was evaluated by detecting 37 non-tuberculous mycobacteria (NTM), and the detection limit of the method was evaluated by genomic DNA of a standard strain H37Rv. Finally, 962 clinical isolates were analyzed with the PMA assay by detecting mutations in rifampin resistance-determining region (RRDR) of rpoB gene, and results were verified with DNA sequencing.

RESULTSAmong 37 NTM strains, three strains showed drug resistant mutation signals. The PMA method could detect down to 30 bacteria per reaction. Sample analysis showed that 186 of 962 isolates were mutants, 751 isolates were wild type and 25 isolates failed to give amplification signals. Among the mutant samples detected, 112 samples from November 2009 to April 2010 were further analyzed by sequencing, as well as 200 wild-type samples. The results showed a complete agreement with the PMA assay except for 5 samples failed in sequence analysis.

CONCLUSIONThe PMA assay is rapid, accurate and easy-to-use, and thus can be used for detection of rifampin-resistant in clinical isolate samples.

Bacterial Proteins ; genetics ; Base Sequence ; DNA Mutational Analysis ; DNA, Bacterial ; genetics ; DNA-Directed RNA Polymerases ; Genotype ; Limit of Detection ; Microbial Sensitivity Tests ; Molecular Sequence Data ; Mutation ; Mycobacterium tuberculosis ; genetics ; isolation & purification ; Polymerase Chain Reaction ; methods ; Reagent Kits, Diagnostic ; Sensitivity and Specificity