Alcohol dehydrogenase coexisted solid-state electrochemiluminescence biosensor for detection of p53 gene

An alcohol dehydrogenase （ADH）-coexisted solidstate electrochemiluminescence （ECL） biosensor for sensitive detection of the p53 gene was developed. The electrode modified by multiwalled carbon nanotubes, Ru（bpy）]2＋3 and polypyrrole （ MWNTs-Ru （bpy） ]2＋3 -PPy ） was prepared to adsorb the ssDNA by electrostatic interactions. Then, the ssDNA recognized the gold nanoparticles （AuNPs）-labeled p53 gene and produced the AuNPs-dsDNA electrode with the AuNPs layer. The AuNPs layer adsorbed the ADH molecules for producing the ECL signal. Thus, the biosensor was based on coupling enzyme substrate reaction with solid-state ECL detection, and it displayed good sensitivity and specificity. The detection limit of the wild type p53 sequence （wtp53） is as low as 0. 1 pmol/L and the discrimination is up to 57. 1% between the wtp53 and the muted type p53 sequence （mtp53）. The amenability of this method to the analyses of p53 from normal and cancer cell lysates is demonstrated. The signal of wtp53 in the MGC-803 gastric cancer cell lysates turns out to be about 61.8% that of the wtp53 in the GES-1 normal gastric mucosal cell lysates, and the concentration of the wtp53 is found to decrease about 59 times. The method is highly complementary to enzyme-linked immunosorbent assay （ELISA）, and it holds promise for the diagnosis and management of cancer.

In Vitro and In Vivo Effects and Safety Assessment of Corn Peptides on Alcohol Dehydrogenase Activities

The in vitro and in vivo effects of corn peptides（CPs） prepared from corn gluten meal by proteolysis with an alkaline protease and fractions of CPs from Sephadex G-15 and G-10 columns on activities of alcohol dehydroge-nase（ADH） were studied. The results show that CPs and fraction 3 of CPs from Sephadex G-10 column enhance in vitro ADH activity. Furthermore, the in vitro accelerating effect of the fraction 3 of CPs on ADH activity was superior to that of glutathione, which was also found even in the presence of ADH inhibitor, such as pyrazole. In the in vivo experiments, the animals were fed with different dosages of CPs and with a dose of Chinese distilled spirit orally, and sacrificed for the measurement of ADH activity. In vivo experimental results indicate that CPS enhanced hepatic ADH activities. To test the safety of CPs as health food, 30 d feeding test was performed. No obvious toxic effects were detected in treated Wistar rats.

Identification and expression patterns of alcohol dehydrogenase genes involving in ester volatile biosynthesis in pear fruit

Alcohol dehydrogenase （ADH） catalyzes the interconversion of aldehydes and their corresponding alcohols, and is a key enzyme in volatile ester biosynthesis. However, little is known regarding ADH and ADH encoding genes （ADHs） in pear. We identified 8 ADHs in the pear＇s genome （PbrADHs） by multiple sequences alignment. The PbrADHs were highly ho- mologous in their coding regions, while were diversiform in structure. 9 introns were predicted in PbrADH3-PbrADH8, while 8 introns, generated through exon fusion and intron loss, were predicted in PbrADH1 and PbrADH2. To study the genetic regulation underlying aroma biogenesis in pear fruit, we determined the PbrADH transcripts, ADH activities and volatile contents of fruits during ripening stage for Nanguoli and Dangshansuli, two cultivars having different aroma characteristics. ADH activity was strongly associated with the transcription of ADH~ in the two cultivars during fruit ripening stage. The higher ester content paralleling to a higher ADH activity was detected in Nanguoli than in Dangshansuli, so it is induced that the lower ester content in Dangshansuli fruit may be the result of weak ADH activity. The present study revealed that total ADH activity and volatile ester production correlated with increased PbrADHstranscript levels. PbrADH6 may contribute to ADH activity catalyzing aldehyde reduction and ester formation in pear fruit.

Selective Affinity Separation of Yeast Alcohol Dehydrogenase by Reverse Micelles with Unbound Triazine Dye

The reversed micelles were formed with cationic cetyltrimethylammonium bromide (CTAB) as surfactant and n-hexanol as cosolvent in the CTAB (50mmol.L-1)/hexanol (15% by volume)/hexane system. Cibacron Blue 3GA (CB) as an affinity ligand in the aqueous phase was directly introduced to the reversed micelles with electrostatic interaction between anionic CB and cationic surfactant. High molecular weight (Mr) protein, yeast alcohol dehydrogenase (YADH, Mr = 141000) from baker's yeast, has been purified using the affinity reversed micelles by the phase transfer method. Various parameters, such as CB concentration, pH and ionic strength, on YADH forward and backward transfer were studied. YADH can be transferred into and out from the reversed micelles under mild conditions (only by regulation of solution pH and salt concentration) with the successful recovery of most YADH activity. Both forward and backward extractions occurred when the aqueous phase pH＞pI with electrostatic attraction between YADH and CTAB. The recovery of YADH activity and purification factor have been improved with addition of a small amount of affinity CB. The recovery of YADH activity obtained was ～99% and the purification factor was about 4.0-fold after one cycle of full forward and backward extraction. The low ionic strength in the initial aqueous phase might be responsible for the YADH transfer into the reversed micellar phase.

Polymorphisms of alcohol dehydrogenase 2 and aldehyde dehydrogenase 2 and colorectal cancer risk in Chinese males

AIM: To evaluate the relationship between drinking and polymorphisms of alcohol dehydrogenase 2 (ADH2) and/or aldehyde dehydrogenase 2 (ALDH2) for risk of colorectal cancer (CRC) in Chinese males. METHODS: A case-control study was conducted in 190 cases and 223 population-based controls. ADH2 Arg47His (G-A) and ALDH2 Glu487Lys (G-A)genotypes were identified by PCR and denaturing high-performance liquid chromatography (DHPLC). Information on smoking and drinking was collected and odds ratio (OR) was estimated. RESULTS: The ADH2 A/A and ALDH2 G/G genotypes showed moderately increased CRC risk. The age- and smoking-adjusted OR for ADH2 A/A relative to G/A and G/G was 1.60 (95% CI=1.08-2.36), and the adjusted OR for ALDH2 G/G relative to G/A and A/A was 1.79 (95% CI=1.19-2.69). Signif icant interactions between ADH2, ALDH2 and drinking were observed. As compared to the subjects with ADH2 G and ALDH2 A alleles, those with ADH2 A/A and ALDH2 G/G genotypes had a signif icantly increased OR (3.05, 95% CI= 1.67-5.57). The OR for CRC among drinkers with the ADH2 A/A genotype was increased to 3.44 (95% CI= 1.84-6.42) compared with non-drinkers with the ADH2 G allele. The OR for CRC among drinkers with the ALDH2 G/G genotype was also increased to 2.70 (95% CI= 1.57-4.66) compared with non-drinkers with the ALDH2 A allele. CONCLUSION: Polymorphisms of the ADH2 and ALDH2 genes are significantly associated with CRC risk. There are also signifi cant gene-gene and gene- environment interactions between drinking and ADH2 and ALDH2 polymorphisms regarding CRC risk in Chinese males.

Alcohol Dehydrogenase Activity in Cultured Cells from Different Tobacco (Nicotiana tabacum L.) Varieties

The activity of alcohol dehydrogenase (ADH) in cultured cells of various tobacco was determined. It was found that significant differences existed in cells of different varieties cultured under normal conditions and as well after treated with exogenous ethanol. The ADH activity had positive relation with the ability of the cells to catabolize exogenous ethanol, indicating that the main function of the ADH in tobacco cells was in the direction of converting ethanol to acetaldehyde.

Achieving Enzyme Stability Using a Simple Fabrication Procedure： The Alcohol Dehydrogenase Example

The use of screen-printing biosensors has been updated in this article as a tool to analyze the electron transfer process involving redox proteins or enzymes. The aim of this research was to fabricate a simple apparatus which allowed the use of the enzymes （in the solid state） to maintain their stability. To prove this concept an enzyme in the solid state was mixed with the carbon ink and this mixture was used to print the working electrode. We choose as proving the alcohol dehydrogenase. The first reason is because it metabolizes the alcohol, which can be present in biological samples of blood, saliva and urine and also in the beverage; the second is that this enzyme is still a challenge to electrochemistry due to having lower stability in sensors. The results show that in this device the enzyme was active and stable during all the experiments and in the experimental conditions that could catalyze the ethanol to acetaldehyde. These devices have the advantage of being disposable, cheap and are easy to fabricate. And also, they do not need expensive tools to be fabricated, they only need 2μL of electrolyte or sample, and they need lower amounts of enzyme to permit electrochemical studies.

A novel alcohol dehydrogenase in the hyperthermophilic crenarchaeon Hyperthermus butylicus

Hyperthermus butylicus is a hyperthermophilic crenarchaeon that produces 1-butanol as an end product.A thermostable alcohol dehydrogenase(ADH)must be present in H.butylicus to act as the key enzyme responsible for this production;however,the gene that encodes the ADH has not yet been identified.A novel ADH,HbADH2,was purified from a cell-free extract of H.butylicus,and its characteristics were determined.The gene that encodes HbADH2 was demonstrated to be HBUT_RS04850 and annotated as a hypothetical protein in H.butylicus.HbADH2 was found to be a primary-secondary ADH capable of using a wide range of substrates,including butyraldehyde and butanol.Butyraldehyde had the highest specificity constant,calculated as k_(cat)/K_(m),with kcat and apparent K_(m) values of 8.00±0.22 s^(-1) and 0.59±0.07 mM,respectively.The apparent Km values for other substrates,including ethanol,1-propanol,2-propanol,butanol,acetaldehyde,propanal,and acetone,were 4.36±0.42,4.69±0.41,3.74±0.46,2.44±0.30,1.27±0.18,1.55±0.20,and 0.68±0.04 mM,respectively.The optimal pH values for catalyzing aldehyde reduction and alcohol oxidation were 6.0 and 9.0,respectively,while the optimal temperature was higher than 90°C due to the increase in enzymatic activity from 60℃ to 90℃.Based on its substrate specificity,enzyme kinetics,and thermostability,HbADH2 may be the ADH that catalyzes the production of 1-butanol in H.butylicus.The putative conserved motif sites for NAD(P)^(+)and iron binding were identified by aligning HbADH2 with previously characterized Fe-containing ADHs.

Genetic polymorphisms in cytochrome P4502E1, alcohol and aldehyde dehydrogenases and the risk of esophageal squamous cell carcinoma in Gansu Chinese males

AIM:To evaluate the association between genetic polymorphisms in CYP2E1, ALDH2 and ADH1B and the risk of esophageal squamous cell carcinoma (ESCC) in a high risk area of Gansu Province, in Chinese males. METHODS: A case-control study was conducted to investigate the genetic polymorphisms of these enzymes (CYP2E1 *c1/*c2, ALDH2 *1/*2 and ADH1B *1/*1 genotypes). A total of 80 esophageal cancer cases and 480 controls were recruited. RESULTS: Compared with controls, cases had a greater prevalence of heavier alcohol consumption (53.8% vs 16.2%) and a higher proportion of alcohol drinkers with > 30 drink-years (28.8% vs 13.5%). Heavier alcohol consumption and alcohol drinking with > 30 drink- years increased the risk of ESCC, with ORs (95% CI) of 3.20 (1.32-9.65) and 1.68 (0.96-3.21). CYP2E1 (*c1/*c1), ALDH2 (*1/*2) and ADH1B (*1/*1) genotype frequencies were higher among patients with squamous cell carcinomas, at a level close to statistical significance (P = 0.014; P = 0.094; P = 0.0001 respectively). There were synergistic interactions among alcohol drinking and ALDH2, ADH1B and CYP2E1 genotypes. The risk of the ESCC in moderate-to-heavy drinkers with an inactive ALDH2 encoded by ALDH2 *1/*2 as well as ADH1B encoded by ADH1B *1/*1 and CYP2E1 encoded by CYP2E1 *c1/*c1 was higher than that in the never/rare-to-light drinkers with an active ALDH2 (*1/*1 genotype) as well as ADH1B (*1/*2 + *2/*2) and CYP2E1 (*c1/*c2 + *c2/*c2) genotypes, with a statistically significant difference; ORs (95% CI) of 8.58 (3.28-22.68), 27.12 (8.52-70.19) and 7.64 (2.82-11.31) respectively. The risk of the ESCC in moderate-to-heavy drinkers with ALDH2 (*1/*2) combined the ADH1B (*1/*1) genotype or ALDH2 (*1/*2) combined the CYP2E1 (*c1/*c1) genotype leads to synergistic interactions, higher than drinkers with ALDH2 (*1/*1) + ADH1B (*1/*2 + *2/*2), ALDH2 (*1/*1) + CYP2E1 (*c1/*c2 + *c2/*c2) respectively , ORs (95% CI) of 7.46 (3.28-18.32) and 6.82 (1.44-9.76) respectively. Individuals with the ADH1B combined the CYP2E1 genotype showed no synergistic interaction. CONCLUSION: In our study, we found that alcohol consumption and polymorphisms in the CYP2E1, ADH1B and ALDH2 genes are important risk factors for ESCC, and that there was a synergistic interaction among polymorphisms in the CYP2E1, ALDH2 and ADH1B genes and heavy alcohol drinking, in Chinese males living in Gansu Province, China.

Alcohol dehydrogenase I expression correlates with CDR1, CDR2 and FLU1 expression in Candida albicans from patients with vulvovaginal candidiasis

Background The most critical mechanism governing drug resistance in Candida albicans （C. albicans） involves efflux pumps, the functionality of which largely depends on energy metabolism. Alcohol dehydrogenase I （ADH1） plays an important role in intracellular energy metabolism. The aim of this study was to explore the relationship between ADH1 and drug resistance in C. albicans. Methods Twenty clinical C. albicans samples isolated from individual patients diagnosed with vulvovaginal candidiasis, and two C. albicans strains obtained from a single parental source （the fluconazole （FLC）-sensitive strain CA-1s and the FLC-resistant strain CA-16R） were included in our study. In accordance with the Clinical and Laboratory Standards Institute （CLSI） M27-A3 guidelines, we used the microdilution method to examine the FLC minimum inhibitory concentrations （MICs） and real-time reverse transcription polymerase chain reaction （RT-PCR） to measure the mRNA expression levels of ADH1 and the azole resistance genes CDR1, CDR2, MDR1, FLU1 and ERG11 in all the isolates. Results A highly significant positive correlation between the mRNA levels of ADH1 and the MICs （r =0.921, P=0.000）, as well as positive correlations between the mRNA level of ADH1 and those of CDR1, CDR2 and FLU1 （rs of 0.704, 0.772 and 0.779, respectively, P 〈0.01）, were observed in the 20 clinical C. albicans samples. The relative expression of ADH1 was upregulated 10.63- to 17.61-fold in all of the drug-resistant isolates. No correlations were found between the mRNA levels of ADH1 and those of MDR1 or ERG11 （P 〉0.05）. The mRNA levels of the examined drug resistance genes were higher in the CA-16R strain than in CA-1s, and the mRNA levels of ADH1 in CA-16R were 11.64-fold higher than those in CA-1s （P 〈0.05）. Conclusions These results suggest that high levels of ADH1 transcription are implicated in FLC resistance in C. albicans and that the mRNA expression levels of ADH1 are positively correlated with those of CDR1, CDR2 and FLU1.

Alcohol dehydrogenase 5 of Helicoverpa armigera interacts with the CYP6B6 promoter in response to 2-tridecanone

Alcohol dehydrogenase 5(ADH5)is a member of medium-chain dehydro-genase/reductase family and takes part in cellular formaldehyde and S-nitrosoglutathione metabolic network.2-tridecanone(2-TD)is a toxic compound in many Solanaceae crops to defend against a variety of herbivory insects.In the broader context of insect development and pest control strategies,this study investigates how a new ADHS from Helicoverpa armigera(HaADH5)regulates the expression of CYP6B6,a gene involved in molting and metamorphosis,in response to 2-TD treatment.Cloning of the HaADH5 complementary DNA sequence revealed that its 1002 bp open reading frame encodes 334 amino acids with a predicted molecular weight of 36.5 kD.HaADH5 protein was purified in the Es-cherichia coli Transetta(pET32a-HaADH5)strain using a prokaryotic expression system.The ability of HaADH5 protein to interact with the 2-TD responsive region within the promoter of CYP6B6 was confirmed by an in vitro electrophoretic mobility shift assay and transcription activity validation in yeast.Finally,the expression levels of both HaADH5 and CYP6B6 were found to be significantly decreased in the midgut of 6th instar larvae after 48 h of treatment with 10 mg/g 2-TD artificial diet.These results indicate that upon 2-TD treatment of cotton bollworm,HaADHS regulates the expression of CYP6B6 by interacting with its promoter.As HaADH5 regulation of CYP6B6 expression may con-tribute to the larval xenobiotic detoxification,molting and metamorphosis,HaADH5 is a.candidate target for controlling the growth and development of cotton bollworm.

Effect of Ionic Liquids on Catalytic Characteristics of Horse Liver Alcohol Dehydrogenase

The catalytic characteristics of horse liver alcohol dehydrogenase （HLADH） in the systems involving ionic liquids （ILs） （BMIm·Cl, BMIm·Br, BMIm·PF6, BMIm·BF4 BMIm·OTf and EMIm·Cl） were examined. HLADH displayed higher oxidation activity towards ethanol in the systems containing BMIm·Cl, BMIm·Br, EMIm·Cl or BMIm·PF6 with proper content than that in the IL-free buffer. An excessive amount of these ILs in the reaction systems resulted in an obvious decline in enzymatic activity. BMIm·BF4 and BMIm·OTf of any content investigated could considerably inhibit the enzyme. The anions of ILs showed significant effect on the activity, kinetic parameters and activation energy of HLADH-mediated ethanol oxidation. Additionally, BMIm·Cl, BMIm·Br, EMIm·Cl and BMIm·PF6 boosted markedly the thermostability of HLADH, while the enzyme was less thermostable in BMIm·BF4 or BMIm·OTf-containing systems. The associated conformational changes in HLADH caused by ILs were examined by UV technique.

Association of alcohol dehydrogenase and aldehyde dehydrogenase 2 genetic polymorphisms with serum lipid profile: meta-analysis of mendelian randomisation studies

Background Alcohol dehydrogenase （ADH） and aldehyde dehydrogenase 2 （ALDH2） are the key en- zymes for alcohol metabolism. Several genetic studies have investigated the association between ADH and ALDH2 genetic polymorphisms and serum lipid profile （SLP）, however, the results were inconsistent. Methods Fourteen articles involving 27,917 participants were included in this meta-analysis. Weighted mean difference （WMD） and 95% confidence intervals （CIs） were presented using random effects model. Publication bias was evaluated by funnel plot and Begg＇s test. In addition, to further explore the heterogeneity, subgroup analysis were performed. Results Overall, there was no association between ADH genetic polymorphisms and SLP with no regard for drinking status. However, compared with ALDH2 wild homozygous genotype, ALDH2 mutant genotypes were associated with significant decrease in serum high density lipoprotein cholesterol （HDL- C） （WMD -1.80 mg/dL, 95% CI -1.88 to -1.72, P 〈 0.001） and total cholesterol （TC） levels （WMD -1.]0 mg/dL, 95% CI -1.59 to -0.62, P 〈 0.001）, and significant increase in serum low density lipoprotein choles- terol （LDL-C） level （WMD 0.30 mg/dL, 95% CI 0.18 to 0.43, P 〈 0.001）. Although there was no significant difference in serum triglyceride level in the overall population, subgroup analysis revealed that compared with ALDH2 ＊ 1 wild homozygote, ALDH2 ＊ 2 allele displayed a significant difference in serum triglyceride level between the female and male （female： WMD 1.69 mg/dl, 95% CI 1.08 to 2.30, P 〈 0.001; male： WMD -6.42 mg/dL, 95% CI -12.15 to -0.68, P = 0.028）. Conclusion ADH genetic polymorphism has no association with SLP, regardless of sex category and drinking status. ALDH2 genetic polymorphism has slight association with HDL-C, LDL-C and TC levels and sex-specific association with serum triglyceride level. Whether or not the association between ADH2 genetic polymorphisms and SLP is resulted from alcohol con-sumption needs further investigation.

Efficient conversion of aromatic and phenylpropanoid alcohols to acids by the cascade biocatalysis of alcohol and aldehyde dehydrogenases

Benzyl and phenylpropanoid acids are widely used in organic synthesis of fine chemicals,such as pharmaceuticals and condiments.However,biocatalysis of these acids has received less attention than chemical synthesis.One of the main challenges for biological production is the limited availability of alcohol dehydrogenases and aldehyde dehydrogenases.Environmental microorganisms are potential sources of these enzymes.In this study,129 alcohol dehydrogenases and 42 aldehyde dehydrogenases from Corynebacterium glutamicum,Pseudomonas aeruginosa,and Bacillus subtilis were identified and explored with various benzyl and phenylpropanoid alcohol and aldehyde substrates,among which four alcohol dehydrogenases and four aldehyde dehydrogenases with broad substrate specificity and high catalytic activity were obtained.Moreover,a cascade whole-cell catalytic system including ADH-90,ALDH-40,and the NAD(P)H oxidase LreNox was established,which showed high efficiency in converting cinnamyl alcohol and p-methylbenzyl alcohol into the respective carboxylic acids.Remarkably,this biocatalytic system can be easily scaled up to gram-level production,facilitating preparation purposes.

Meta-analysis reveals up-regulation of cholesterol processes in non-alcoholic and down-regulation in alcoholic fatty liver disease

AIM To compare transcriptomes of non-alcoholic fatty liver disease(NAFLD) and alcoholic liver disease(ALD) in a meta-analysis of liver biopsies.METHODS Employing transcriptome data from patient liver biopsies retrieved from several public repositories we performed a meta-analysis comparing ALD and NAFLD.RESULTS We observed predominating commonalities at the transcriptome level between ALD and NAFLD,most prominently numerous down-regulated metabolic pathways and cytochrome-related pathways and a few up-regulated pathways which include ECM-receptor interaction,phagosome and lysosome.However some pathways were regulated in opposite directions in ALD and NAFLD,for example,glycolysis was down-regulated in ALD and up-regulated in NAFLD.Interestingly,we found rate-limiting genes such as HMGCR,SQLE and CYP7A1 which are associated with cholesterol processes adversely regulated between ALD(down-regulated) and NAFLD(up-regulated).We propose that similar phenotypes in both diseases may be due to a lower level of the enzyme CYP7A1 compared to the cholesterol synthesis enzymes HMGCR and SQLE.Additionally,we provide a compendium of comparative KEGG pathways regulation in ALD and NAFLD.CONCLUSION Our finding of adversely regulated cholesterol processes in ALD and NAFLD draws the focus to regulation of cholesterol secretion into bile.Thus,it will be interesting to further investigate CYP7A1-mediated cholesterol secretion into bile-also as possible drug targets.The list of potential novel biomarkers may assist differential diagnosis of ALD and NAFLD.

Positive effect of ethanol-induced Lactococcus lactis on alcohol metabolism in mice

It is well known that exposure to environmental stresses could enhance the adaptability of bacteria and up-regulate the expression of a variety of oxidative stress-related genes and antioxidant enzymes.It is unclear whether the adaptability of microorganisms formed naturally in special environments could transfer to other organisms.The study aimed to evaluate the effects of untreated and ethanol-induced Lactococcus lactis intracellular extracts(U-IE and E-IE)on alcohol metabolism in mice.The positive effects of E-IE on alcohol metabolism in mice were revealed by the enhanced latency of loss of righting reflex(LORR),the reduced duration of LORR,the decrease of blood alcohol concentration,as well as the elevation of alcohol dehydrogenase(ADH)activities in the stomach and liver tissues.Furthermore,the potential benefits of E-IE on the liver were evaluated by biochemical parameters including the activities of serum transaminase,the levels of antioxidant enzymes,and the pathological changes of liver tissue.The present work put forward a new point that appropriate ethanol stress could enhance the intracellular ADH activity of L.lactis,and its intracellular extracts could continue to enhance alcohol metabolism in mice.

Cloning and functional characterization of two cDNAs encoding NADPH-dependent 3-ketoacyl-CoA reductased from developing cotton fibers

Genes encoding enzymes involved in biosynthesis of very long chain fatty acids were significantly up-regulatedduring early cotton fiber development. Two cDNAs, GhKCR1 and GhKCR2 encoding putative cotton 3-ketoacyl-CoAreductases that catalyze the second step in fatty acid elongation, were isolated from developing cotton fibers. GhKCR1and 2 contain open reading frames of 963 bp and 924 bp encoding proteins of 320 and 307 amino acid residues,respectively. Quantatitive RT-PCR analysis showed that both these genes were highly preferentially expressed duringthe cotton fiber elongation period with much lower levels recovered from roots, stems and leaves. GhKCR1 and 2showed 30%-32% identity to Saccharomyces cerevisiae Ybr159p at the deduced amino acid level. These cotton cDNAswere cloned and expressed in yeast haploid ybr159w? mutant that was deficient in 3-ketoacyl-CoA reductase activity.Wild-type growth rate was restored in ybr159w? cells that expressed either GhKCR1 or 2. Further analysis showed thatGhKCR1 and 2 were co-sedimented within the membranous pellet fraction after high-speed centrifugation, similar to theyeast endoplasmic reticulum marker ScKar2p. Both GhKCR(s) showed NADPH-dependent 3-ketoacyl-CoA reductaseactivity in an in vitro assay system using palmitoyl-CoA and malonyl-CoA as substrates. Our results suggest thatGhKCR1 and 2 are functional orthologues of ScYbr159p.

Genetic polymorphisms of ADH2 and ALDH2 association with esophageal cancer risk in southwest China

AIM＂ TO evaluate the impact of alcohol dehydrogenase 2 （ADH2） and aldehyde dehydrogenase 2 （ALDH2） polymorphisms on esophageal cancer risk. METHODS;One hundred and ninety-one esophageal cancer patients and 198 healthy controls from Yanting County were enrolled in this study. ADH2 and ALDH2 genotypes were examined by polymerase-chain-reaction with the confronting-two-pair-primer （PCR-CTPP） method. Unconditional logistic regression was used to calculate the odds ratios （OR） and 95% confidence interval （95% CI）. RESULTS; Both ADH2＊1 allele and ALDH2＊1/＊2 allele showed an increased risk of developing esophageal cancer. The adjusted OR （95% CI） for ADH2＊1 allele compared with ADH2＊2/＊2 was 1.65 （95% CI = 1.02-2.68） and 1.67 （95% CI = 1.02-2.72） for ALDH2＊1/＊2 compared with ALDH2＊1/＊1. A significant interaction between ALDH2 and drinking was detected regarding esophageal cancer risk, the OR was 1.83 （95% CI = 1.13-2.95）. Furthermore, when compared with ADH2＊2/＊2 and ALDH2＊1/＊1 carriers, ADH2＊1 and ALDH2＊2 carriers showed an elevated risk of developing esophageal cancer among non-alcohol drinkers

rAAV/ABAD-DP-6His attenuates oxidative stressinduced injury of PC12 cells

Our previous studies have revealed that amyloidβ（Aβ）-binding alcohol dehydrogenase （ABAD） decoy peptide antagonizes Aβ42-induced neurotoxicity. However, whether it improves oxidative stress injury remains unclear. In this study, a recombinant adenovirus constitutively secreting and expressing Aβ-ABAD decoy peptide （rAAV/ABAD-DP-6His） was successfully constructed. Our results showed that rAAV/ABAD-DP-6His increased superoxide dismutase activity in hydro-gen peroxide-induced oxidative stress-mediated injury of PC12 cells. Moreover, rAAV/ABAD-DP-6His decreased malondialdehyde content, intracellular Ca2＋concentration, and the level of reactive oxygen species. rAAV/ABAD-DP-6His maintained the stability of the mitochondrial membrane potential. In addition, the ATP level remained constant, and apoptosis was reduced. Overall, the results indicate that rAAV/ABAD-DP-6His generates the fusion peptide, Aβ-ABAD decoy peptide, which effectively protects PC12 cells from oxidative stress injury induced by hy-drogen peroxide, thus exerting neuroprotective effects.

The novel amyloid-beta peptide aptamer inhibits intracellular amyloid-beta peptide toxicity

Amyloid β peptide binding alcohol dehydrogenase （ABAD） decoy peptide （DP） can competitively antagonize binding of amyloid β peptide to ABAD and inhibit the cytotoxic effects of amyloid β peptide. Based on peptide aptamers, the present study inserted ABAD-DP into the disulfide bond of human thioredoxin （TRX） using molecular cloning technique to construct a fusion gene that can express the TRX1-ABAD-DP-TRX2 aptamer. Moreover, adeno-associated virus was used to allow its stable expression. Immunofluorescent staining revealed the co-expression of the transduced fusion gene TRX1-ABAD-DP-TRX2 and amyloid β peptide in NIH-3T3 cells, indicating that the TRXl-ABAD-DP-TRX2 aptamer can bind amyloid β peptide within cells. In addition, cell morphology and MTT results suggested that TRX1-ABAD-DP-TRX2 attenuated amyloid β peptide-induced SH-SY5Y cell injury and improved cell viability. These findings confirmed the possibility of constructing TRX-based peptide aptamer using ABAD-DP. Moreover, TRXl-ABAD-DP-TRX2 inhibited the cytotoxic effect of amyloid β peptide.