Biomedical subjects

Rong Jiang

Publications and source records attributed to Rong Jiang.

At least 19 recordsLinked to original sources

PubMed2026

Development of molecular markers associated with saline-alkali tolerance in rapeseed (Brassica napus L.).

A total of 947 saline-alkaline tolerance-related molecular markers and a 5K cGPS genotyping chipwere developed, providing practical tools for marker-assisted selection and molecular design breeding of saline-alkaline-tolerant rapeseed. Rapeseed (Brassica napus L.) has relatively strong tolerance to saline-alkaline stress and shows great potential for the sustainable utilization and improvement of saline-alkaline soils. However, the breeding of highly tolerant cultivars still mainly depends on conventional hybridization combined with phenotype-based selection, which constrains breeding efficiency. In this study, previously reported saline-alkaline tolerance-related genes from rapeseed, rice, maize, wheat, sorghum, and Arabidopsis were collected. Candidate gene-based association analysis enabled the development of molecular markers and a genotyping chip. A total of 483 significantly associated genes were identified, among which 355 genes contained favorable haplotypes. Molecular markers were successfully developed for 275 genes, including 746 KASP and 201 InDel marker pairs, and four marker pairs were randomly selected for validation. In addition, a 5K cGPS liquid-phase chip (HZSW-cGPS-BRNAP-04), was developed and showed a high call rate and excellent reproducibility in genotyping. These markers and the chip are expected to improve the breeding efficiency of saline-alkaline-tolerant rapeseed cultivars. Overall, this study provides useful tools for early-generation evaluation and marker-assisted selection (MAS), and provides a foundation for molecular design breeding of saline-alkali-tolerant rapeseed.

Brassica napus↗

PubMed2007

Novel syntheses of chiral beta- and gamma-amino acid derivatives utilizing N-protected (aminoacyl)benzotriazoles from aspartic and glutamic acids.

Friedel-Crafts reactions of N-protected (alpha-aminoacyl)benzotriazoles with hetero- and benzenoid- aromatics give alpha-amino ketones that can be reduced by either triethyl silane or sodium borohydride to form the corresponding beta- and gamma-amino acid derivatives. The preservation of chirality throughout this process is confirmed by chiral HPLC results.

Amino Acids↗

PubMed2006

Long-term inhibition of myocardial infarction by postconditioning during reperfusion.

Cardioprotection with postconditioning has been well demonstrated after a short period of reperfusion. This study tested the hypothesis that postconditioning reduces infarct size, vascular dysfunction, and neutrophil accumulation after a long-term reperfusion. Canines undergoing 60 min left anterior descending artery (LAD) occlusion were divided into two control groups of either 3 h or 24 h of full reperfusion and two postconditioning groups with three 30 s cycles of reperfusion and re-occlusion applied at the onset of either 3 h or 24 h of reperfusion. Size of the area at risk (AAR) and collateral blood flow during ischemia were similar among groups. In controls, infarct size as percentage of the AAR (30 +/- 3 vs. 39 +/- 2* %) by TTC staining, superoxide anion generation from the post-ischemic coronary arteries by lucigenin-enhanced chemiluminescence [(89 +/- 5 vs. 236 +/- 27* relative light units (RLU/mg)], and neutrophil (PMN) accumulation by immunohistochemical staining in the AAR (52 +/- 11 vs. 84 +/- 14* cells/mm(2) myocardium) significantly increased between 3 and 24 h of reperfusion. Postconditioning reduced infarct size (15 +/- 4 and 27 +/- 3.6 %), superoxide anion generation (24 +/- 4 and 43 +/- 11 RLU/mg), and PMN accumulation (19 +/- 6 and 45 +/- 8 cells/mm(2) myocardium) in the 3 and 24 h reperfusion groups relative to time-matched controls. These data suggest that myocardial injury increases with duration of reperfusion; reduction in infarct size and attenuation in inflammatory responses with postconditioning persist after a prolonged reperfusion. * p < 0.05 24 vs. 3 h control; p < 0.05 postconditioning vs. time-matched control.

Animals↗

PubMed2006

Inferring population parameters from single-feature polymorphism data.

This article is concerned with a statistical modeling procedure to call single-feature polymorphisms from microarray experiments. We use this new type of polymorphism data to estimate the mutation and recombination parameters in a population. The mutation parameter can be estimated via the number of single-feature polymorphisms called in the sample. For the recombination parameter, a two-feature sampling distribution is derived in a way analogous to that for the two-locus sampling distribution with SNP data. The approximate-likelihood approach using the two-feature sampling distribution is examined and found to work well. A coalescent simulation study is used to investigate the accuracy and robustness of our method. Our approach allows the utilization of single-feature polymorphism data for inference in population genetics.

Arabidopsis↗

PubMed2006

Association mapping with single-feature polymorphisms.

We develop methods for exploiting "single-feature polymorphism" data, generated by hybridizing genomic DNA to oligonucleotide expression arrays. Our methods enable the use of such data, which can be regarded as very high density, but imperfect, polymorphism data, for genomewide association or linkage disequilibrium mapping. We use a simulation-based power study to conclude that our methods should have good power for organisms like Arabidopsis thaliana, in which linkage disequilibrium is extensive, the reason being that the noisiness of single-feature polymorphism data is more than compensated for by their great number. Finally, we show how power depends on the accuracy with which single-feature polymorphisms are called.

Algorithms↗

PubMed2006

Infarct-sparing effect of myocardial postconditioning is dependent on protein kinase C signalling.

OBJECTIVE: Using non-selective and selective protein kinase C (PKC) epsilon and delta isoform inhibitors, we tested the hypothesis that the cardioprotective phenotype invoked by postconditioning (postcon) is dependent on PKC signalling. Furthermore, we determined whether postconditioning alters pPKCepsilon and/or pPKCdelta in cytosolic and mitochondrial fractions. METHODS: Male Sprague-Dawley rats underwent 30 min left coronary artery (LCA) occlusion followed by 3 h of reperfusion. Rats were randomised to the following groups: Untreated, no intervention either before or after LCA occlusion; Postcon, 3 cycles of 10-s full reperfusion and 10-s re-occlusion, initiated immediately at the onset of reperfusion; Chelerythrine (non-selective PKC inhibitor, 5 mg/kg)+/-postcon; Rottlerin (PKCdelta inhibitor, 0.3 mg/kg)+/-postcon; KIE1-1 (PKCepsilon inhibitor, 3.8 mg/kg)+/-postcon. A subset of rats was employed to assess pPKCepsilon and/or pPKCdelta in sham, Isch/RP (30-min LCA occlusion followed by 30-min reperfusion), and postcon-treated hearts. RESULTS: Infarct size, expressed as area of necrosis as a percentage of the area at risk, AN/AAR (%), was significantly reduced by postcon compared to control (untreated) rats (39+/-2% vs. 53+/-1% in control, P<0.001). Treatment with chelerythrine alone or the PKCepsilon antagonist KIE1-1 alone at reperfusion had no effect on infarct size compared to control. In contrast, the infarct-sparing effect of postcon was abrogated by non-selective PKC inhibition and PKCepsilon antagonism (50+/-2% and 50+/-1%, respectively, P<0.002). Inhibition of PKCdelta reduced infarct size to values comparable to that in postcon group (36+/-3% vs. 39+/-2%). However, postcon in the presence of PKCdelta inhibitor did not enhance the infarct-sparing effects (38+/-2%). In addition, pPKCepsilon in postcon hearts was significantly higher in the total cell homogenate (10338+/-1627 vs. 4165+/-608 in Isch/RP, arbitrary units), and pPKCdelta translocation to mitochondria was significantly less (>2-fold decrease) compared to Isch/RP. CONCLUSION: These data suggest that postcon modulates PKC during early reperfusion by increasing PKCepsilon expression and translocation to a site other than the outer mitochondrial membrane, and limits translocation of PKCdelta to mitochondria and associated deleterious signalling.

Acetophenones↗

PubMed2006

Adsorption dynamics of binary mixture of Gemini surfactant and opposite-charged conventional surfactant in aqueous solution.

The maximum bubble pressure technique has been used to study the adsorption kinetics of binary mixtures of an anionic Gemini surfactant C9pPHCNa with a cationic conventional surfactant C10TABr in aqueous solutions. The dynamic surface tension data were analyzed using the revised Ward and Tordai equations as well as the micelle dissociation kinetic model suggested by Joos et al. The apparent diffusion coefficient Da below the cmc, the adsorption barrier epsilona and the micelle dissociation constant kmic were obtained. The Da s at short times and at long times were respectively 0.2-16 x 10(10) and 0.08-0.9 x 10(10) m2s(-1), the latter corresponded to the adsorption barrier epsilona of 10-20 kJ mol(-1). The minimum epsilona appeared at the mole fraction of C9pPHCNa (alpha1, on a surfactant-only basis) in the bulk solution being 0.33. The kmic s of the mixed micelles were about 16-2300 s(-1). The most stable mixed micelles were formed at alpha1=0.2 rather than at alpha1=0.33 owing to great discrepancy of hydrophobicity between the two components. These results indicated that the composition of mixed solution was an important factor affecting the adsorption kinetics and the micelle stability.

Journal Article↗

PubMed2006

Thoracic Surgery Directors Association Award. Cobalt chloride pretreatment attenuates myocardial apoptosis after hypothermic circulatory arrest.

BACKGROUND: Deep hypothermic circulatory arrest (DHCA) causes myocyte injury as a consequence of ischemia and reperfusion. Previous studies have shown that hypoxia or hypoxia-mimetic agents (cobalt chloride [CoCl2] or deferoxamine [DFX]) limit myocyte necrosis by upregulating the transcription factor hypoxia-inducible factor. However, it remains unknown whether these agents attenuate myocardial apoptosis after DHCA. This study tested the hypotheses (1) that hypoxia, DFX, or CoCl2 preconditioning attenuates myocardial apoptosis during DHCA; and (2) that the protective mechanism involves the altered expression of apoptosis regulatory proteins pAkt (antiapoptotic), Bcl-2 (antiapoptotic), and Bax (proapoptotic). METHODS: Anesthetized neonatal piglets were randomly assigned to four groups (n = 6 in a group): control (NaCl injection); hypoxia (pO2 of 30 to 40 mm Hg for 3 hours); DFX injection; or CoCl2 injection. Twenty-four hours later, the animals underwent cardiopulmonary bypass (CPB) and 110 minutes of DHCA. One week after CPB, percentage of apoptotic myocytes (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling [TUNEL] assay) and expression of the pAKT, Bcl-2, and Bax were assessed by Western blot. RESULTS: Although preconditioning with hypoxia and DFX failed to show a protective benefit, CoCl2 pretreatment significantly attenuated myocardial apoptosis (9.3% +/- 4.1%) versus controls (33.8% +/- 9.7%, p = 0.042). That was associated with increased myocardial pAkt expression (0.19 +/- 0.006 in CoCl2 versus 0.12 +/- 0.008 in control, p < 0.001). The expression of Bcl-2 was also significantly higher in the CoCl2 group (0.15 +/- 0.02) versus control (0.11 +/- 0.01, p = 0.007), whereas Bax expression was lower (0.34 +/- 0.04 versus 0.54 +/- 0.03 for control, p < 0.001). CONCLUSIONS: Preconditioning with CoCl2 before prolonged DHCA in neonatal piglets attenuates myocardial apoptosis by mechanisms involving phosphorylation of Akt, upregulation of the antiapoptotic protein Bcl-2, and decreased expression of the proapoptotic protein Bax.

Animals↗

PubMed2006

[A IL-6R antagonist 2520A produced by a fungal species].

AIM: To isolate IL-6R antagonists from the cultured broth of the strain Torulomyces ovatus. METHODS: Various column chromatographyes were used to separate and purify the compounds with IL-6R antagonist activity. The spectral data and physic-chemical properties were measured for structure identification. RESULTS: One compound namely 2520 was isolated from the cultured broth of Torulomyces ovatus. CONCLUSION: 2520A is a known compound (ferrichrome). It is first reported about its antagonistic activity of IL-6R and identification of iron atom in its structure.

Anti-Bacterial Agents↗

PubMed2006

[Synergistic effects of total saponins of panax ginseng in combination with hematopoietic growth factor on proliferation and differentiation of CD34(+) cells ex vivo].

To investigate the effects of total saponins of panax ginseng (TSPG) in combination with hematopoietic growth factors (HGF) on proliferation and differentiation of CD34(+) cells ex vivo, the purified CD34(+) cells from cord blood and bone marrow were expanded by various concentrations of TSPG with combination of cytokines in liquid culture systems and the expanded cell number, CD34(+) cell number, CD33(+) cell ratio, the numbers of total CFC and hematopoietic progenitor cell number were detected. The results showed that TSPG (10 - 70 microg/ml) could raise the expanded cell number, CD34(+) cell number, and the numbers of total CFC, TSPG 50 microg/ml was identified as the most potent stimulating concentration, and increased total nucleated cells to (2470.5 +/- 79.96) x 10(3), CFC to (53.96 +/- 4.286) x 100% and CD34(+) cells to (21.86 +/- 3.094) x 100%; TSPG (10 - 50 microg/ml) could raise the colony formation rate of CFU-GM, TSPG (20 microg/ml) induced the best effect on granulocytopoietic differentiation committed of CD34(+) cells. It is concluded that the optimal concentration of TSPG can promote CD34(+) cells to proliferate and differentiate by cooperating with hematopoietic growth factors.

Antigens, CD34↗

PubMed2006

[Effect of high volume hemofiltration on pulmonary surfactant protein in endotoxin induced acute lung injury in dog].

OBJECTIVE: To explore the effect of high volume hemofiltration (HVHF) on pulmonary surfactant protein (SP) in endotoxin induced acute lung injury (ALI) in dogs. METHODS: Sixteen healthy male mongrel dogs were given lipopolysaccharide(LPS 650 mug/kg) via central vein within 30 minutes. After the reproduction of the model, they were divided into two groups randomly (n=8). One group received the treatment of HVHF and mechanical ventilation (MV, treatment group), while another received only MV (model group). Parameters of arterial blood gas and respiratory mechanics were recorded at basic values, after reproduction of the experimental model, and 1, 2 and 4 hours after HVHF. Content of SP-B in lung tissue homogenate was measured by protein Western blot. RESULTS: After injection of LPS, partial pressure of oxygen in artery (PaO(2)) and PaO(2)/fractional concentration of inspired oxygen (FiO(2)) began to decrease (both P<0.05). PaO(2)/FiO(2) <300 mm Hg (1 mm Hg=0.133 kPa) when ALI was reproduced. PaO(2) and PaO(2)/FiO(2) were higher in treatment group than those in model group 4 hours after HVHF (both P<0.01). Inspiratory resistance of airway (Raw) and peak inspiratory pressure (PIP) in model group were kept stable after MV. Lung dynamic compliance (Cdyn) and lung total compliance (Ctot) in model group were both decreased while ventilatory work of breathing (WOBvent) increased 4 hours after MV (all P<0.01). All parameters in the treatment group were kept stable and differences in Cdyn and Ctot were significant at 4 hours after HVHF compared to model group (P<0.01 and P<0.05). Content of SP-B in lung tissue homogenate was significantly higher in treatment group than that in model group (P<0.01). CONCLUSION: HVHF could effectively increase the content of SP-B in lung to prevent aggravation of respiratory mechanics and improve oxygenation.

Acute Lung Injury↗

PubMed2005

N-Tfa- and N-Fmoc-(alpha-aminoacyl)benzotriazoles as chiral C-acylating reagents under Friedel-Crafts reaction conditions.

Chiral N-Tfa- and N-Fmoc-protected (alpha-aminoacyl)benzotriazoles 1a-j undergo Friedel-Crafts-type reactions with indole, N-methylindole, pyrrole, N-methylpyrrole, and benzene in the presence of AlCl(3) in efficient two-step sequences leading to enantiomerically pure alpha-amino N-heterocyclic ketones 2, 3, 5, 6, and 7 or diketone 4. In the absence of a reactive partner, Phe- and Trp-derivatives 1a, 1d undergo intramolecular cyclization to afford 12 and 13, again with retention of chirality.

Journal Article↗

PubMed2005

Postconditioning via stuttering reperfusion limits myocardial infarct size in rabbit hearts: role of ERK1/2.

Emerging evidence suggests that restoration of blood flow in a stuttering manner may limit lethal myocardial ischemia-reperfusion injury. However, the mechanisms contributing to this phenomenon, termed postconditioning (post-C), remain poorly defined. Our aim was to test the hypothesis that activation of classic "survival kinases," phosphatidylinositol 3-kinase (PI3-kinase) and/or extracellular signal-regulated kinase (ERK)1/2, may play a role in post-C-induced cardioprotection. In protocol 1, isolated buffer-perfused rabbit hearts underwent 30 min of sustained coronary artery occlusion and were randomized to receive abrupt reperfusion (controls) or four cycles of 30 s of reperfusion and 30 s of reocclusion before full restoration of flow (post-C). Protocol 2 was identical except control and postconditioned hearts received the PI3-kinase inhibitor LY-294002 (protocol 2A) or the ERK1/2 antagonist PD-98059 (protocol 2B) throughout the first 25 min of reperfusion, whereas in protocol 3, myocardial samples were obtained during the early minutes of reflow from additional control, postconditioned, and nonischemic sham hearts for the assessment, by standard immunoblotting, of phospho-Akt (downstream target of PI3-kinase) and phospho-ERK. Protocols 1 and 2 corroborated that infarct size (delineated by tetrazolium staining and expressed as a percent of risk region) was reduced in postconditioned hearts vs. control hearts and also revealed that post-C-induced cardioprotection was maintained despite LY-294002 treatment but was abrogated by PD-98059. These pharmacological data were supported by protocol 3, which showed increased immunoreactivity of phospho-ERK but not phospho-Akt with post-C. Thus our results implicate the involvement of ERK1/2 rather than PI3-kinase/Akt in the reduction of infarct size achieved with post-C.

Animals↗

PubMed2005

Adverse outcomes associated with inappropriate drug use in nursing homes.

BACKGROUND: Little empirical evidence exists regarding the influence and outcomes of inappropriate medication use among elderly nursing home residents. OBJECTIVE: To identify the prevalence of inappropriate medication use among elderly patients in Georgia nursing homes using the Beers criteria and identify the relationship between inappropriate drug use and the likelihood of an adverse health outcome. METHODS: A cohort design was used to review 1117 patient medical records in 15 Georgia nursing homes with a high risk of polypharmacy. Prevalence of inappropriate medication use among elderly patients, as defined by the Beers criteria, was estimated. The adverse health outcomes of hospitalizations, emergency department visits, or deaths were identified from Medicaid claims data. RESULTS: A total of 519 (46.5%) patients received at least one inappropriate medication and 143 (12.8%) patients experienced at least one adverse health outcome. Logistic regression revealed that the total number of medications taken (OR 1.139, 95% CI 1.105 to 1.173) significantly increased the likelihood of receiving an inappropriate drug, while having a diagnosis of "dementia" (OR 0.748, 95% CI 0.565 to 0.991) decreased the likelihood. Inappropriate medication use increased the likelihood of experiencing at least one adverse health outcome more than twofold (OR 2.34, 95% CI 1.61 to 3.40). Propoxyphene use alone was significantly associated with the occurrence of an adverse health outcome (OR 2.39, 95% CI 1.54 to 3.71). CONCLUSIONS: Inappropriate drug use was common in our study cohort. Inappropriate use of medication in the elderly, particularly propoxyphene, is associated with a higher risk of adverse health outcomes.

Aged↗

PubMed2005

An epidemiological investigation of off-label anticonvulsant drug use in the Georgia Medicaid population.

PURPOSE: The primary objective was to determine the prevalence of off-label anticonvulsant drug use in the Georgia Medicaid population and establish what percentage of this off-label use is evidence-based. The second objective was to investigate differences in the prevalence of off-label use among anticonvulsants marketed before and after 1993. The third objective was to identify patient and physician characteristics associated with off-label use. METHOD: The study design was a retrospective study utilizing pharmacy, inpatient, outpatient and long-term care claims linked with eligibility files for persons with Georgia Medicaid benefits in 1999 through 2000. An anticonvulsant recipient was considered an off-label anticonvulsant user if their anticonvulsant use did not match age or medical diagnoses in the product label. An evidence-based off-label use was defined as off-label anticonvulsant use supported by at least one randomized controlled clinical trial. Logistic regression analysis was used to identify patient and physician characteristics associated with off-label use. RESULTS: 34 676 (71.3%) of 48 648 patients on one or more anticonvulsants received an off-label prescription for an anticonvulsant. Gabapentin was the anticonvulsant most widely used off-label (86%). After accounting for labeled and all evidence-based uses for the six most frequently prescribed anticonvulsants, there was a moderate to large percentage of anticonvulsant use not supported by any evidence from controlled trials (range: 19.09-57.07%). The most common comorbidities among patients prescribed the top six anticonvulsants were diabetes mellitus, depression, schizophrenia and pain. Anticonvulsants launched after 1993 had a higher prevalence of off-label use than anticonvulsants marketed before 1993. Off-label drug use varied by age with children and adolescents being the most likely to receive an off-label anticonvulsant. Compared with other practitioners, neurologists were more likely to prescribe anticonvulsants off-label. CONCLUSIONS: The anticonvulsant off-label use in the Georgia Medicaid population is very high (71%). Only a modest proportion of these off-label uses are supported by evidence from controlled trials.

Adolescent↗

PubMed2005

Myocardial protection in reperfusion with postconditioning.

Reperfusion is the definitive treatment for coronary occlusive disease. However, reperfusion carries the potential to exacerbate lethal injury, termed 'reperfusion injury'. Studies have suggested that reperfusion injury events are triggered during the early moments of reflow, and determine, in part, the severity of downstream manifestations of postischemic injury, including endothelial dysfunction, infarction and apoptosis. The application of brief iterative episodes of reflow (reoxygenation) and reocclusion (ischemia, hypoxia) at the immediate onset of reperfusion, which has been termed 'postconditioning' by the authors, reduces many manifestations of postischemic injury, notably infarct size, apoptosis, coronary vascular endothelial injury and reperfusion arrhythmias. Cardioprotection with postconditioning has been reported to be comparable with that observed using the gold standard maneuver ischemic preconditioning. In contrast to preconditioning, which exerts its effects primarily during the index ischemia, postconditioning appears to exert its effects during reperfusion alone. Postconditioning modifies the early phase of reperfusion in ways that are just beginning to be understood. It appears to first: reduce the oxidant burden and consequent oxidant-induced injury; secondly, attenuate the local inflammatory response to reperfusion; and thirdly, engage end effectors and signaling pathways implicated in other cardioprotective maneuvers, such as ischemic and pharmacologic preconditioning. Postconditioning seems to trigger the upregulation of survival kinases principally known to attenuate the pathogenesis of apoptosis and possibly necrosis. The postconditioning phenomenon has been reproduced by a number of independent laboratories and has been observed in both large and small animal in vivo models, as well as in ex vivo and cell culture models. In contrast to preconditioning, postconditioning may have widespread clinical application because it can be applied during reperfusion at the point of service for angioplasty, stenting, cardiac surgery and organ transplantation.

Humans↗

PubMed2005

Cloning, expression and characterization of the Ste6 gene encoding a UDP-glucose dehydrogenase in Streptomyces.

Streptomyces sp. 139 was identified to produce a new exopolysaccharide Ebosin (139A) with antirheumatic arthritis activity in vivo. The Ebosin biosynthesis gene cluster(31.3 kb; GenBank Accession Number: AY131229) containing 22 ORFs (ste1-ste22) of Streptomyces sp. 139 had been reported previously. In this paper,we present experimental evidence for the identity of the ste6 gene product as a UDP-glucose dehydrogenase (UDPGDH). With pET-30a as vector,the gene was cloned and expressed in Escherichia coli BL21 (DE3). The expressed protein was purified to homogeneity by His-Bind resin affinity chromatograpy and it was able to catalyze UDP-glucose to UDP-glucuronic acid. To evaluate the function of ste6, the gene was disrupted by a single-crossover homologous recombination event and the result showed that ste6 is required in Ebosin biosynthesis.

Amino Acid Sequence↗

PubMed2005

[Cloning and expression of UDP-glucose-4-epimerase gene from Streptomyces and characteristics of the enzyme].

The ste 19 gene is identified to encode a UDP-Glucose-4-epimerase by data base comparison and experimental validation. The enzyme catalyzes the interconversion of UDP-Glucose and UDP-Galactose. The gene amplified by PCR with the total DNA of Streptomyces sp. 139 as template was cloned into plasmid pET30a at Xho I - Nde I sites. After the recombinant plasmid was transformed into E. coli BL21 (DE3) and induced by IPTG, the protein was expressed as high as 26% of the total cell proteins and dominantly as soluble protein form. The high GC content (73.8%) and the preferential usage of G or C as third base of codons (96.2%) seems not to affect its good expression in E. coli BL21 (DE3). The purity of the recombinant protein purified by Ni2+ affinity chromatography is 92.9% by HPLC analysis. Enzyme activity assay shows the recombinant protein is a UDP-Glucose-4-epimerase and its activity is not dependent on exogenous NAD+. The above research lays a very good foundation for study on functions of the ste 19 gene in Ebosin biosynthesis.

Cloning, Molecular↗