Forty-one strains of Streptococcus pneumoniae were isolated at Seoul National University Children's Hospital from 1991 to 1997. Isolates were divided into six groups based on MICs of three quinolones, ciprofloxacin, ofloxacin and norfloxacin. Sequencing showed that the isolates which were intermediately resistant to three quinolones or resistant to at least one kind of quinolone had one missense mutation, Lys137-->Asn(AAG-->AAT) substitution in the ParC subunit of topoisomerase IV without additional mutation in QRDR of the GyrA subunit of DNA gyrase. In conclusion, the ParC subunit of DNA topoisomerase IV is the primary target site for fluoroquinolone in S. pneumoniae and Lys137-->Asn substitution renders the quinolone resistance in S. pneumoniae.
DNA Topoisomerase (ATP-Hydrolysing)/genetics* ; Drug Resistance, Microbial/genetics* ; Human ; Isoenzymes/genetics* ; Mutation/genetics* ; Quinolones* ; Streptococcus pneumoniae/genetics

OBJECTIVETo investigate whether the titrate-resistant acid phosphatase 5 (ACP5) gene polymorphisms were associated with the occurrence or curve severity of adolescent idiopathic scoliosis (AIS).

METHODSThere were 372 AIS patients from January 2006 to December 2008 and 239 normal controls from March 2005 to August 2006 were recruited. The Cobb angles were ≥ 10° in all AIS patients. Using the haplotype data of Han population from the Hapmap Project, two tag SNPs (rs2229531, rs2071484) were defined for ACP5 gene. PCR-restriction fragment length polymorphism was used for the genotyping.

RESULTSNo polymorphism in rs2229531 was found in this study. The genotype and allele frequency distribution in rs2071484 were similar between AIS patients and normal controls (χ(2) = 3.336 and 1.438, P > 0.05). The mean maximum Cobb angles of different genotypes of rs2071484 in ACP5 gene were 38° ± 19° in AA, 34° ± 14° in AG and 38° ± 21° in GG, which were similar with each other among AIS patients who reached skeletal maturity or received surgery treatment (P = 0.157).

CONCLUSIONThe ACP5 gene is neither associated with the occurrence nor the curve severity of AIS.

Acid Phosphatase ; genetics ; Adolescent ; Child ; Female ; Humans ; Isoenzymes ; genetics ; Male ; Polymorphism, Genetic ; Scoliosis ; genetics ; Tartrate-Resistant Acid Phosphatase

This study intends to obtain recombinant proteins of ALT1 and ALT2 isozymes by using genetic recombination technology. Monoclonal antibodies ALT1 and ALT2 with high specificity and high activity were prepared and screened (ALT1 monoclonal antibody has been successfully prepared and published). The localization, distribution and expression of ALT1 and ALT2 isozymes in human tissues were discussed. The ALT2 genes were amplified from human liver cancer cell (HepG2) by RT-PCR method. The mature ALT2 gene was subcloned into the pET32a-ALT2 prokaryotic expression vector. Its ligation product was transformed into BL21(DE3) competent cells, and transformed into competent cells to express ALT2 proteins induced by IPTG. The recombinant proteins of ALT2 were purified by nickel column (Ni⁺) affinity chromatography. Balb/c mice were immunized with recombinant proteins of ALT2. Positive serum mouse spleen cells and myeloma cells SP2/0 were selected for cell fusion. The positive cell lines were selected by indirect ELISA and subcloned by limited dilution method. Affinity chromatography was used to purify ALT2 antibodies. The expression and distribution of ALT2 in human normal tissues were detected by RT-PCR and Western blotting. Results show that the expression of ALT isoenzyme in tissues was almost the same at gene mRNA level and protein level. ALT1 is highly expressed in liver, kidney and skeletal muscle, and moderately expressed in gastrointestinal smooth muscle. ALT2 is highly expressed in fat, skeletal muscle and myocardium, and is poorly expressed in gastrointestinal smooth muscle. Immunohistochemical studies show that ALT1 is highly expressed in hepatocytes, renal medullary tubules and muscle fibers, ALT2 is highly expressed in adipocytes and myocardial cells, and ALT1 and ALT2 in gastrointestinal tissues are mainly expressed in mucosa of upper intestinal wall region. The results showed that the isoenzymes ALT1 and ALT2 were mainly expressed in the mucosa of the upper part of the intestinal wall. It is widely distributed in the tissues, providing theoretical basis for understanding the mechanism of ALT activity increase under different pathological conditions.
Alanine Transaminase ; Animals ; Cloning, Molecular ; Humans ; Isoenzymes/genetics* ; Liver ; Mice ; Recombinant Proteins

The terminal differentiation of malignant melanoma cells is known to be induced by activating cAMP signaling pathway with alpha-MSH or cAMP analogues. However, sustained activation of cAMP signaling system that induces the differentiation of melanoma cells, also induces the desensitization of the pathway at the receptor level. Nevertheless, the adaptation of adenylate cyclase (AC) expression by sustained activation of cAMP signaling system has not been clearly understood. This study was performed to examine whether the sustained activation of cAMP system induce changes in the expression AC isoforms as an adaptation mechanism. Treatment of B16/F10 murine melanoma cells with 100 mM forskolin for 6 days resulted in differentiation, melanin accumulation and increased expression of tyrosine hydroxylase mRNA. In the forskolin-treated melanoma cells, change in expression of various AC isoform at the transcription level was detected by reverse-transcription polymerase chain reaction (RT-PCR). Expression of AC isoform mRNA: ACI, III, VI, VII, and IX increased to the level of 196-392% of the control whereas the level of ACII was decreased by 30%. The cAMP concentration was increased both in basal and alpha-MSH stimulated cells, but the AC activity was decreased in the forskolin treated cells. Thus, these results suggest that sustained activation of cAMP system induces differential expression of AC isoforms, which results in increase of cAMP accumulation.
Adenylate Cyclase/*genetics ; Animal ; Cell Differentiation ; Cyclic AMP/*metabolism ; Forskolin/*pharmacology ; Isoenzymes/genetics ; Melanoma, Experimental/*enzymology/*pathology ; Mice ; Signal Transduction

Acetohydroxyacid synthase (AHAS) catalyses the first reaction in the pathway for synthesis of the branched-chain amino acids. AHAS is the target for sulfonylurea, imidazolinone and other AHAS-inhibitor herbicides. Herbicides-resistant AHAS genes have potential application in plant transgenetic engineering and development of new generation herbicide. The AHAS isozyme genes ilvBN, ilvGM and ilvIH were cloned from metsulfuron-methyl resistant strain Klebsiella sp. HR11 and metsulfuron-methyl sensitive strain Klebsiella pneumoniae MGH 78578. Homologous sequences comparison indicated that the differences in AHAS isozyme genes at amino acid levels between strain HR11 and strain MGH 78578 were mainly on the large subunits of ilvBN and ilvGM. The three AHAS isozyme genes from HR11 and MGH 78578 were ligated into the expression vector pET29a(+) and expressed in Escherichia coli BL21, respectively. The results of enzyme inhibition assay showed that only ilvBN and ilvGM from strain HR11 showed strong resistance to AHAS-inhibitor herbicides, while ilvIH from strain HR11 and ilvBN, ilvGM and ilvIH from strain MGH78578 were sensitive to AHAS-inhibitor herbicides.
Acetolactate Synthase ; chemistry ; genetics ; Escherichia coli ; genetics ; metabolism ; Gene Expression ; Genes, Bacterial ; drug effects ; Herbicide Resistance ; genetics ; Herbicides ; pharmacology ; Imidazolines ; pharmacology ; Isoenzymes ; genetics ; Klebsiella ; genetics ; Sulfonylurea Compounds ; pharmacology

A laccase gene (lacD) from the basidiomycete Trametes sp. 420 was heterologously expressed in Pichia pastoris in two ways, resulting in two recombinant enzymes of rLacDx with native N-terminus and rLacDe with eight additional amino acid residues at N-terminus. The yields of rLacDx and rLacDe in shaken-flask cultures after an 18-day growth were 1.21 x 10(5) u/L and 7.38 x 10(4) u/L, respectively, as determined with 2,2'-azinobis(3-ethylbenzothia-zoline- 6-sulfonic acid) (ABTS) as substrate. The yield of rLacDx was further increased to 2.39 x 10(5) u/L under high-density fermentation while the production process was decreased to 7.5 days. In addition, rLacDx and rLacDe exhibited similar enzymatic characters in oxidizing substrate guaiacol, and were stable at 50 degrees C and at a pH range from 3 to 10. However, the specific activity of rLacDx (1761 u/mg) for ABTS was higher than that of rLacDe (1122 u/mg), and the apparent Km value of rLacDx (427 microM) was less than that of rLacDe (604 microM).
Cloning, Molecular ; Fermentation ; Isoenzymes ; biosynthesis ; genetics ; Laccase ; biosynthesis ; genetics ; Pichia ; genetics ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification ; Trametes ; enzymology ; genetics

Previous studies have suggested that glutathione S-transferase (GST) genotypes may play a role in determining susceptibility to cervical cancer, though the data have often been conflicting. The objective of this study was to examine the effect of GSTP1 polymorphism on cervical carcinogenesis. The studied subjects, patients who were pathologically diagnosed with invasive cervical cancer yielding positive results for human papillomavirus (HPV) (n=342), were compared to healthy, normal, female controls (n=707). DNA from peripheral blood samples from studied subjects whose GSTP1 specific sequences had been determined by PCR with allele-specific primers were reviewed in comparison with the normal controls. The genetic susceptibility of GSTP1 (11q 13.1) in cervical carcinogenesis was determined by examining the effect of gene and environmental factors by the different histopathologic types of invasive cervical cancers. In assessing polymorphism GSTP1, the percentages of individuals homozygous for the A allele, homozygous for the G allele, and heterozygous for the two alleles were 66.8%, 3.9%, and 29.3%, respectively, in the control group, and 64.3%, 4.1%, and 31.6%, respectively, among in women with cervical cancer. Compared with GSTP1 G allele positive (GA or G/G), the odds ratio (OR) (95% confidence interval) for GSTP1 A/A was 1.0 (0.7 - 1.4) for invasive cervical cancer. However, the risk increased with GSTP1 A/A among ever smokers (3.9, 1.7 - 8.9, p-value=0.0012) compared with GSTP1 G allele positive among nonsmokers. In particular, this risk was higher among women with squamous cell carcinoma (4.7, 2.0 - 10.8, p=0.0003). Polymorphism of GSTP1 among smoking women was associated with a higher risk of developing cervical cancer.
Adult ; Aged ; Cervix Neoplasms/*etiology/genetics ; Female ; Glutathione Transferase/*genetics ; Human ; Isoenzymes/*genetics ; Loss of Heterozygosity ; Middle Age ; Polymorphism (Genetics) ; Risk ; Smoking

OBJECTIVESTo construct a prokaryotic recombinant vector for mouse lactate dehydrogenase-C and to detect its expression in BL21.

METHODSThe coding sequence of mouse lactate dehydrogenase subunit C was amplified from mouse testis RNA with specific primers, and cloned into pGEX-2T after the restriction digestion with BamH I and EcoR I. GST fusion protein was expressed after induction with IPTG.

RESULTSSequencing and restriction digestion of the recombinant plasmid revealed the existence of coding sequence for mouse lactate dehydrogenase subunit C. A protein band of about 60,000 could be induced by IPTG in the recombinant plasmid.

CONCLUSIONSThe coding sequence of mouse lactate dehydrogenase subunit C was introduced into the pGEX-2T plasmid and a GST-fused protein could be induced at a high level.

Animals ; Escherichia coli ; genetics ; Glutathione Transferase ; genetics ; Isoenzymes ; genetics ; L-Lactate Dehydrogenase ; genetics ; Male ; Mice ; Recombinant Fusion Proteins ; biosynthesis ; Spermatozoa ; enzymology

OBJECTIVETo explore the relationship between genetic polymorphisms of the ethanol metabolizing enzymes and the occurrence of alcoholic liver disease (ALD).

METHODSSixty-five healthy male controls and 165 alcoholisms (including 122 ALD patients and 43 male alcohol abusers without liver complications defined as alcohol-dependent) were analyzed by polymerase chain reaction and hybridized with oligonucleotide microarray to detect the polymorphisms of the ethanol metabolizing enzymes genes.

RESULTSThe frequencies of alcohol dehydrogenase gene 2 * 1 ( ADH2 * 1 ) allele were shown as 37.69%, 46.51% and 59.02% in control, alcohol-dependent and ALD groups respectively; while those of ADH2 * 2 allele were shown as 62.31 %, 53.49% and 40.98% respectively. No ADH2 * 3 was detected in any of the subjects. The frequency of ADH2 * 1 was significantly higher in alcoholisms (ALD group and alcohol-dependent group) than in healthy controls ( P < 0. 01), and significantly higher in ALD group than in alcohol-dependent group ( P < 0.05) . The frequency of ADH3 * 2 was significantly higher in alcohol-dependents than in healthy controls ( P < 0.05) . The frequencies of ALDH2 * 2 allele mutation were significantly lower in alcoholisms than that in the healthy controls, and the deference between ALD group and alcohol-dependent group was significant. No homozygotes for the mutant ALDH2 * 2 allele were found in either alcoholic groups.

CONCLUSIONSPolymorphic ADH2, ADH3 and ALDH2 genes can affect the propensity for alcohol drinking in Chinese. The alleles of ADH2 * 2, ADH3 * 1 and ALDH2 * 2 are most likely to play a protective role against excessive consumption. ADH2 * 2 and ALDH2 X 2 may contribute to susceptibility for ALD.

Alcohol Dehydrogenase ; genetics ; Aldehyde Oxidoreductases ; genetics ; Genotype ; Humans ; Isoenzymes ; genetics ; Liver Diseases, Alcoholic ; genetics ; Male ; Oligonucleotide Array Sequence Analysis ; Polymorphism, Genetic

BACKGROUNDCigarette smoking is the major risk factor for chronic obstructive pulmonary disease (COPD). However, only 10% - 20% of chronic heavy cigarette smokers develop symptomatic disease. COPD is most likely the result of complex interactions between environmental and genetic factors. Genetic susceptibility to COPD might depend on the variations in enzyme activities that detoxify cigarette smoke products, such as microsomal epoxide hydrolase (mEH) and glutathione S-transferase (GST). In this study, we investigated the relationship between polymorphisms in the genes encoding mEH and glutathione S-transferase P1 (GSTP1) and COPD in a Chinese population.

METHODSPolymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed to find mEH polymorphism in exon 3 (Tyr113-->His), exon 4 (His139-->Arg) and GSTP1 polymorphism in exon 5 (Ile105-->Val) in 100 COPD patients and 100 age- and sex-matched healthy controls.

RESULTSThe proportion of mEH exon 3 heterozygotes was significantly higher in patients with COPD than that in the control subjects (42% vs 32%). The odds ratio (OR) adjusted by age, sex, body mass index (BMI) and cigarette years was 2.96 (95% CI 1.24 - 7.09). There was no marked difference in very slow activity genotype versus other genotypes between COPD patients and the controls. When COPD patients were non-smokers, the OR of very slow activity genotype versus other genotypes was more than 1.00; and when COPD patients were smokers (current smokers and ex-smokers), the OR was less than 1.00. There was no significant difference in GSTP1 polymorphism adjusted by age, sex, BMI and smoking between COPD patients and the controls.

CONCLUSIONSmEH exon 3 heterozygotes might be associated with susceptibility to COPD in China. The interaction might exist between mEH genotype and smoke. The gene polymorphism for GSTP1 might not be associated with susceptibility to COPD in the Chinese population.

Aged ; Epoxide Hydrolases ; genetics ; Female ; Genotype ; Glutathione S-Transferase pi ; Glutathione Transferase ; genetics ; Humans ; Isoenzymes ; genetics ; Male ; Middle Aged ; Mutation ; Polymorphism, Genetic ; Pulmonary Disease, Chronic Obstructive ; etiology ; genetics