(), as a typical intracellular pathogen, possesses several putative restriction-modification (R-M) systems, which restrict exogenous DNA's entry, such as bacterial phage infection. Here, we investigate Rv2528c, a putative Mrr-like type IV restriction endonuclease (REase) from H37Rv, which is predicted to degrade methylated DNA that contains m6A, m5C, etc. Rv2528c shows significant cytotoxicity after being expressed in BL21(DE3)pLysS strain.
View Article and Find Full Text PDFToxin-antitoxin (TA) systems are the major mechanism for persister formation in (). Previous studies found that HigBA2 (Rv2022c-Rv2021c), a predicted type II TA system of , could be activated for transcription in response to multiple stresses such as anti-tuberculosis drugs, nutrient starvation, endure hypoxia, acidic pH, etc. In this study, we determined the binding site of HigA2 (Rv2021c), which is located in the coding region of the upstream gene (), and the conserved recognition motif of HigA2 was characterized via oligonucleotide mutation.
View Article and Find Full Text PDFAssembly-line polyketide synthases (PKSs) are molecular factories that produce diverse metabolites with wide-ranging biological activities. PKSs usually work by constructing and modifying the polyketide backbone successively. Here, we present the cryo-EM structure of CalA3, a chain release PKS module without an ACP domain, and its structures with amidation or hydrolysis products.
View Article and Find Full Text PDFType II thioesterases typically function as editing enzymes, removing acyl groups that have been misconjugated to acyl carrier proteins during polyketide secondary metabolite biosynthesis as a consequence of biosynthetic errors. NRRL 3882 produces the pyrrole polyether ionophoric antibiotic, and we have identified the presence of a putative type II thioesterase-like sequence, , within the biosynthetic gene cluster involved in the antibiotic's synthesis. However, targeted gene mutagenesis experiments in which was inactivated in the organism did not lead to a decrease in calcimycin production but rather reduced the strain's production of its biosynthetic precursor, cezomycin.
View Article and Find Full Text PDFCalcimycin, N-demethyl calcimycin, and cezomycin are polyether divalent cation ionophore secondary metabolites produced by A thorough understanding of the organization of their encoding genes, biosynthetic pathway(s), and cation specificities is vitally important for their efficient future production and therapeutic use. So far, this has been lacking, as has information concerning any biosynthetic relationships that may exist between calcimycin and cezomycin. In this study, we observed that when a Cal ( mutant) derivative of a calcimycin-producing strain of (NRRL 3882) was grown on cezomycin, calcimycin production was restored.
View Article and Find Full Text PDFCalcimycin is a unique ionophoric antibiotic that is widely used in biochemical and pharmaceutical applications, but the genetic basis underlying the regulatory mechanisms of calcimycin biosynthesis are unclear. Here, we identified the gene, which encodes a novel TetR family transcriptional regulator and exerts a negative effect on calcimycin biosynthesis. Disruption of in NRRL 3882 led to significantly increased calcimycin and its intermediate cezomycin.
View Article and Find Full Text PDFThe gene encodes a secretory protein that can inhibit Elk1 transcriptional activity via the ERK1/2 pathway. In the current study, RNA hybridization was used to detect the gene expression in multiple organ cancer and cancer-adjacent normal tissue. The results showed that the expression level of varies across different tissues.
View Article and Find Full Text PDFG-patch domain containing 2 (GPATC2), a human gene that is highly expressed in the testes, was implicated as a novel cancer/testis antigen. The present study investigated GPATC2 expression in a number of human cell lines and rat tissues, and its potential biological function in 293T cells. Semi‑quantitative reverse transcription-polymerase chain reaction analysis showed that GPATC2 was widely expressed in 15 human cell lines (representing different lineages) and in 11 different rat tissues, and that the GPATC2 mRNA relative expression level was significantly higher in the testis than it was in other tissues.
View Article and Find Full Text PDFSpermatogenesis is a complicated and poorly understood process that relies on the precise regulation of the self-renewal and differentiation of spermatogonia. In many organisms, microRNAs (miRNAs) are involved in multiple developmental processes as critical regulators of transcriptional and post-transcriptional gene silencing. This study investigated the expression pattern of miRNAs in type B spermatogonia cells (BSc) and primary spermatocytes (PSc) of mice, using a high-throughput small RNA sequencing system.
View Article and Find Full Text PDFTransmembrane protein 174 (TMEM174) mRNA is easily detectable in human kidney tissues and activates AP-1 and promotes 293T cell proliferation. In the present study, RNA hybridization was used to detect TMEM174 gene expression in various malignant renal cancer and normal renal tissues. The results showed that TMEM174 exhibits differential expression in renal tissues, with a high positive rate of expression in squamous cell carcinoma with necrosis, papillary renal cell carcinoma and transitional cell carcinoma, and a low positive rate of expression in clear cell carcinoma, interstitial nephritis, undifferentiated carcinoma, retroperitoneal metastatic clear cell carcinoma, adrenal gland metastatic clear cell carcinoma, pelvic cavity metastatic chromophobe carcinoma, severe atypical hyperplasia of transitional epithelium and hyperplasia.
View Article and Find Full Text PDFThe zinc finger-homeodomain transcription factor, δ-crystallin enhancer factor 1 (δEF1) has been identified as a regulatory factor involved in the promotion of breast cancer cell proliferation via the downregulation of p21 and the upregulation of cyclin-dependent kinase-2 (CDK2) and CDK4 expression. However, the molecular mechanisms underlying the regulation of CDK4 expression by δEF1 have not yet been elucidated. The present study demonstrated that the ectopic expression of δEF1 in MDA-MB-231 breast cancer cells significantly increased the activity of the CDK4 promoter.
View Article and Find Full Text PDFExp Ther Med
November 2013
Transmembrane protein 174 (TMEM174) is a type III transmembrane protein with no clear signal peptide. The N and C terminals are located inside the cell. Our previous study demonstrated high expression of TMEM174 in the kidney and its potential involvement in renal cancer based on its capacity to stimulate cell proliferation.
View Article and Find Full Text PDFLM23, a gene expressed specifically in the testis in a stage-specific manner, has a diverse range of functions that are important in both the life and death of spermatogenic cells. The aim of this study was to further investigate the expression of LM23 in the developing rat testis and the biological function of LM23 in proliferation and antiapoptosis in vitro. Semiquantitative reverse transcription (RT)-PCR and real-time PCR were used to examine the expression of LM23 in testis at different developmental stages.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
September 2013
The five-membered aromatic nitrogen heterocyclic pyrrole ring is a building block for a wide variety of natural products. Aiming at generating new pyrrole-containing derivatives as well as to identify new candidates that may be of value in designing new anticancer, antiviral, and/or antimicrobial agents, we employed a strategy on pyrrole-containing compound mutasynthesis using the pyrrole-containing calcimycin biosynthetic gene cluster. We blocked the biosynthesis of the calcimycin precursor, 3-hydroxy anthranilic acid, by deletion of calB1-3 and found that two intermediates containing the pyrrole and the spiroketal moiety were accumulated in the culture.
View Article and Find Full Text PDFCalcimycin is a rare divalent cation specific ionophore antibiotic that has many biochemical and pharmaceutical applications. We have recently cloned and sequenced the Streptomyces chartreusis calcimycin biosynthesis gene cluster as well as identified the genes required for the synthesis of the polyketide backbone of calcimycin. Additional modifying or decorating enzymes are required to convert the polyketide backbone into the biologically active calcimycin.
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
January 2011
Based on the long term (1999-2008) monitoring of air temperature and relative humidity and of the occurrence and epidemiological trend of Marssonina blotch in the main apple-production area of Shaanxi Province, this paper analyzed the occurrence time, pathogenesis regularity, and epidemiological level of Marssonina blotch, with the 1- and 3-dimensional models for predicting Marssonina blotch under effects of ten-day mean air temperature (T) and relative humidity (Hm) constructed. In study area, the development of Marssonina blotch was mainly affected by environment factors. This disease spread rapidly in field in July and August, causing orchard defoliation, and the harm persisted until September.
View Article and Find Full Text PDFBackground And Objective: Connective tissue growth factor (CTGF) has been identified as playing critical roles in fibrosis and is a promising therapeutic target. In a previous study, we used a phage display library to develop a humanized single-chain variable fragment antibody (scFv) against CTGF. In the present study, the protective effect of anti-CTGF scFv against bleomycin (BL)-induced pulmonary fibrosis was investigated in mice.
View Article and Find Full Text PDFExcessive expression of CTGF (connective tissue growth factor)/CCN2 has been observed in many fibrotic diseases. The inhibition of the CTGF/CCN2 by antibody has been shown to be clinically useful for the management of fibrosis. A phage display humanized single-chain Fv antibody library was screened using CTGF/C (CTGF/CCN2 C-terminal domain) as the target.
View Article and Find Full Text PDFConnective tissue growth factor (CTGF) plays a crucial role in the formation and development of hepatic fibrosis. The aim of this study was to establish a method for CTGF determination in order to investigate the level of CTGF in the sera of patients with hepatitis B virus, and to assess the correlation between CTGF concentration and stage of hepatic fibrosis. A CTGF C-terminal region gene was obtained by RT-PCR of human mesangial kidney cells and inserted into pET-32a((+)) vector.
View Article and Find Full Text PDFs-thanatin, an analogue of thanatin, was synthesised by substituting the fifteenth amino acid threonine with serine and showed broad antimicrobial activity against Gram-negative and Gram-positive bacteria. To evaluate its antimicrobial activity against a multidrug-resistant (MDR) clinical isolate as well as its anti-endotoxin activity, its lipopolysaccharide (LPS)-binding and -neutralising activity in vitro and its therapeutic efficacy in an experimental model of septic shock caused by a MDR clinical isolate of Escherichia coli were studied. The ability of s-thanatin to bind or neutralise LPS from E.
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