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Na Wu,
Xi Yang,
Ruifen Zhang,
Jun Li,
Xue Xiao,
Yongfei Hu,
Yanfei Chen,
Fengling Yang, Na Lu,
Zhiyun Wang, [......],
Yulan Liu,
Baohong Wang,
Charlie Xiang,
Yuezhu Wang,
Fangqing Zhao,
George F Gao,
Shengyue Wang,
Lanjuan Li,
Haizeng Zhang,
Baoli Zhu
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ABSTRACT: The human gut microbiota is a complex system that is essential to the health of the host. Increasing evidence suggests that the gut microbiota may play an important role in the pathogenesis of colorectal cancer (CRC). In this study, we used pyrosequencing of the 16S rRNA gene V3 region to characterize the fecal microbiota of 19 patients with CRC and 20 healthy control subjects. The results revealed striking differences in fecal microbial population patterns between these two groups. Partial least-squares discriminant analysis showed that 17 phylotypes closely related to Bacteroides were enriched in the gut microbiota of CRC patients, whereas nine operational taxonomic units, represented by the butyrate-producing genera Faecalibacterium and Roseburia, were significantly less abundant. A positive correlation was observed between the abundance of Bacteroides species and CRC disease status (R = 0.462, P = 0.046 < 0.5). In addition, 16 genera were significantly more abundant in CRC samples than in controls, including potentially pathogenic Fusobacterium and Campylobacter species at genus level. The dysbiosis of fecal microbiota, characterized by the enrichment of potential pathogens and the decrease in butyrate-producing members, may therefore represent a specific microbial signature of CRC. A greater understanding of the dynamics of the fecal microbiota may assist in the development of novel fecal microbiome-related diagnostic tools for CRC.
Microbial Ecology 06/2013; · 2.91 Impact Factor
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ABSTRACT: Our previous studies revealed that gambogic acid (GA), the major active ingredient of gamboge, possessed antiangiogenic activities. In this study, we further explored the mechanism of inhibition effects of GA in tumor angiogenesis. The results of luciferase, RT-PCR, and ELISA assays indicated that GA significantly decreased transcription activation, mRNA expression, and secretion of VEGF in hypoxia. We detected that GA had no effect on mRNA level of HIF-1α which targets VEGF gene, but the increase of HIF-1α protein expression in hypoxia was repressed by GA, which can be reversed by proteasomal inhibitor MG132 and siRNA of VHL. But GA exhibited no effect on expression of VHL both in normoxia and hypoxia. HIF prolyl hydroxylases (PHD enzymes) act as oxygen sensors regulating HIF, and hence angiogenesis. Our results showed that GA potencially enhanced level of PHD2, the most important HIF hydroxylase, and showed no effect on PHD1 and PHD3. Transient transfection of siRNA of PHD2 could eliminate GA-induced VEGF secretion increase. Growth of HepG2 xenografts in BALB/cA nude mice was inhibited by GA and angiogenesis was repressed significantly in tumor xenografts by immunohistochemical staining of CD-31, a vascular endothelial marker, accompanied with decrease of HIF-1α and increase of PHD2 expression in tissue extracts. This work provides the demonstration that GA shows anti-angiogenic effects via inhibiting PHD2-VHL-HIF-1α pathway.
European journal of pharmaceutical sciences: official journal of the European Federation for Pharmaceutical Sciences 03/2013; · 2.61 Impact Factor
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ABSTRACT: Key points Wogonoside induces cell cycle arrest and differentiationWogonoside acts by changing PLSCR1 expression and subcellular localization in the nucleus and by PLSCR1-related molecular events.
Blood 03/2013; · 9.90 Impact Factor
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ABSTRACT: A soil metagenomic library was constructed and screened for clones that conferred fosfomycin resistance. A novel protein with 46 % identity to UDP-N-acetylglucosamine enolpyruvyl transferase (MurA) from Desulfuromonas acetoxidans DSM 684 (GenBank accession number: ZP_01311756) was identified. Multiple sequence alignment revealed that the novel protein was a natural MurA, in which an aspartic acid instead of a cysteine was located in the active site. An Asp120Cys mutant of Escherichia coli was constructed from the subclone through site-specific mutagenesis, and minimum inhibitory concentration of fosfomycin for the resistant subclone and its mutant were determined. These results showed that fosfomycin resistance was a result of the aspartic acid in the active site. Analysis of all existing MurA sequences revealed that MurAs with an active site aspartic acid that can confer fosfomycin resistance occur in ~14 % of bacteria.
Biotechnology Letters 11/2012; · 1.68 Impact Factor
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Gong Cheng,
Yongfei Hu,
Yeshi Yin,
Xi Yang,
Chunsheng Xiang,
Baohong Wang,
Yanfei Chen,
Fengling Yang,
Fang Lei,
Na Wu, Na Lu,
Jing Li,
Quanze Chen,
Lanjuan Li,
Baoli Zhu
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ABSTRACT: The human gut microbiota has a high density of bacteria that are considered a reservoir for antibiotic resistance genes (ARGs). In this study, one fosmid metagenomic library generated from the gut microbiota of four healthy humans was used to screen for ARGs against seven antibiotics. Eight new ARGs were obtained: one against amoxicillin, six against d-cycloserine, and one against kanamycin. The new amoxicillin resistance gene encodes a protein with 53% identity to a class D β-lactamase from Riemerella anatipestifer RA-GD. The six new d-cycloserine resistance genes encode proteins with 73-81% identity to known d-alanine-d-alanine ligases. The new kanamycin resistance gene encodes a protein of 274 amino acids with an N-terminus (amino acids 1-189) that has 42% identity to the 6'-aminoglycoside acetyltransferase [AAC(6')] from Enterococcus hirae and a C-terminus (amino acids 190-274) with 35% identity to a hypothetical protein from Clostridiales sp. SSC/2. A functional study on the novel kanamycin resistance gene showed that only the N-terminus conferred kanamycin resistance. Our results showed that functional metagenomics is a useful tool for the identification of new ARGs.
FEMS Microbiology Letters 07/2012; 336(1):11-6. · 2.04 Impact Factor
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ABSTRACT: To better understand the molecular mechanisms and evolution of drug resistance in Mycobacterium tuberculosis (M. tuberculosis), we performed a genomic sequence based scanning of drug resistance-associated loci for multidrug-resistant (MDR) and extensively drug-resistant (XDR) M. tuberculosis strains.
Forty-five pairs of primers covering known drug resistance-associated loci compiled in the TBDReaMDB database were designed to perform the analysis of drug resistance-associated mutations for 14 M. tuberculosis clinical isolates from TB patients in China. Genetic diversity and evolutionary analysis was done using concatenated nucleotide sequences of drug resistance-associated loci.
Forty-four types of mutations were identified in 14 M. tuberculosis clinical isolates. Average nucleotide diversity for drug resistance-associated loci increased in the M. tuberculosis isolates as the drug resistance increased (π = 0, π = 0.00021, and π = 0.00028 for susceptible, MDR, and XDR isolates, respectively). The dN/dS ratios for coding regions of drug resistance-associated genes in MDR and XDR isolates were 2.73 and 1.83, respectively. MDR and XDR isolates were distributed sporadically on different branches in the phylogenetic trees.
Our study provides supporting evidence to demonstrate that the MDR- and XDR-M. tuberculosis strains have evolved independently driven by positive selection.
The Journal of infection 06/2012; 65(5):412-22. · 4.13 Impact Factor
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ABSTRACT: Autophagy is a tightly-regulated catabolic process that involves the degradation of intracellular components via lysosomes. Although the pivotal role of autophagy in cell growth, development, and homeostasis has been well understood, its function in cancer prevention and intervention remains to be delineated. The aim of this study was to investigate the function and mechanism of autophagy induced by oroxylin A, a natural mono-flavonoid extracted from Scutellariae radix. We found for the first time that oroxylin A induced Beclin 1-mediated autophagy in human hepatocellular carcinoma HepG2 cells. Time-lapse video microscopy and western blotting studies showed that treatment of cells with 80 μM oroxylin A resulted in the conversion of water soluble MAP-LC3 (LC3-I) to the lipidated and autophagosome-associated form (LC3-II) after 12hours; then autophagosome-lysosome fusion and lysosome degradation after 24 hours was required in oroxylin A-mediated cell death. This induction was associated with the suppressing of PI3K-PTEN-Akt-mTOR signaling pathway by oroxylin A. Our results also showed that autophagy took place before noticeable apoptosis can be observed. It was further demonstrated that oroxylin A-triggered autophagy contributed to cell death using over-expression of autophagy-related gene (Atg5 and Atg7) and inhibition of autophagy by siBeclin 1 and 3-methyladenine (3-MA). In vivo study, oroxylin A inhibited xenograft tumor growth and induced obvious autophagy in tumors. Taken together, we conclude that oroxylin A exhibits autophagy-mediated antitumor activity in a dose and time-dependent manner in vivo and in vitro. These findings define and support a novel function of autophagy in promoting death of hepatocellular carcinoma cells.
Cellular signalling 04/2012; 24(8):1722-32. · 4.09 Impact Factor
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ABSTRACT: Flavonoid is an important group of natural products which exerted anticancer effects against various cancers. III-10 is a newly synthesized flavonoid with a pyrrolidinyl and a benzyl group substitution. It shares a same carbon skeleton with flavonoid which indicates that it may also have potential anticancer activity. To investigate whether III-10 could express anticancer effect on human U937 leukemia cells through differentiation induction, a series of experiments were processed. MTT and trypan-blue excluding assays showed that III-10 possessed growth and viability inhibition effects on U937 cells. Giemsa staining was implemented to observe the morphologic changes of U937 cells after III-10 treatment. Nitroblue tetrazolium (NBT) reduction assay and cell surface antigen flow cytometry were carried out to figure out the way III-10 induced U937 cells to differentiate. These experiments revealed that III-10 could induce U937 cells to differentiate into monocyte-like cells. Western blots and immunofluorescence were performed to inspect the possible underlying mechanism. The results revealed that differentiation-related proteins phospholipids scramblase 1 (PLSCR1) and promyelocytic leukemia protein (PML) were up-regulated after III-10 treatment. And III-10 stimulated PLSCR1 and PML probably through activation of protein kinase Cδ (PKCδ). All these results suggested that III-10 was a prospective anticancer compound and was requisite to be proceeded further investigation.
European journal of pharmaceutical sciences: official journal of the European Federation for Pharmaceutical Sciences 04/2012; 45(5):648-56. · 2.61 Impact Factor
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ABSTRACT: Matrix metalloproteinases (MMPs) play important roles in the invasion and migration of cancer cells. In this study, we used in vitro and in vivo assays to examine the inhibitory effects of oroxylin A, one of the main bioactive flavonoid extracted from Scutellaria radix, on the human breast carcinoma cell MDA-MB-231 invasion and migration. We found that oroxylin A can suppress cell adhesion, invasion and migration in a concentration-dependent manner. Moreover, oroxylin A led to the reduction of the activity and expression levels of MMP-2 and MMP-9 in gelatin zymography, real-time PCR and western blotting analysis. Further elucidation of the mechanism revealed that oroxylin A increased the expression of tissue inhibitor of metalloproteinase-2 (TIMP-2), the endogenous inhibitor of MMP-2, and repressed the phorbol-12-myristate-13-acetate (PMA)-induced translocation of protein kinase Cδ (PKCδ), phosphorylation of extracellular signal-regulated kinase (ERK1/2) and binding activity of the transcription factor activator protein-1 (AP-1) which are upstream signaling molecules in MMP-9 expression. Our results also indicated that oroxylin A inhibited the lung metastasis of murine melanoma cell B16-F10 in vivo. Therefore, we proposed that oroxylin A might be developed as a therapeutic potential candidate for the treatment of cancer metastasis.
Toxicology Letters 03/2012; 209(3):211-20. · 3.23 Impact Factor
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ABSTRACT: It is still debatable whether intracoronary (IC) administration of glycoprotein IIb/IIIa inhibitors (GPIs) is superior to intravenous (IV) administration for patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI).
We performed a meta-analysis of randomized controlled clinical trials. A literature search was conducted for relevant trials. Primary end-points were short-term (1-3 months) and mid-/long-term (6/12 months) major adverse cardiovascular events (MACEs) (mortality, reinfarction, target vessel revascularization [TVR]). Secondary end-points were thrombolysis in myocardial infarction (TIMI) grade flow, TIMI myocardial perfusion grade (TMPG) flow, left ventricular ejection fraction (LVEF) within 2 weeks, and bleeding complication.
Twelve studies were included in the meta-analysis. IC administration of GPIs did not decrease short-term mortality (OR: 0.71, 95% CI: 0.41-1.23, P = 0.22) and reinfarction rate (OR: 0.76, 95% CI: 0.45-1.29, P = 0.31) compared with IV administration. There was a trend toward reduction of short-term TVR rate in IC group compared with IV group but not reaching statistical significance (OR: 0.57, 95% CI: 0.31-1.04, P = 0.07). IC administration of GPIs significantly increased TIMI grade 3 flow (OR: 1.48, 95% CI: 1.06-2.06, P = 0.02) and TMPG grade 2-3 flow (OR: 2.63, 95% CI: 1.53-4.51, P = 0.0004) compared with IV administration. No significant difference was observed in long-term MACEs rate, LVEF, and bleeding complication between the 2 groups.
IC administration of GPIs in patients with ACS undergoing PCI can significantly increase target coronary flow and myocardial reperfusion without increasing the risk of bleeding complication, but cannot improve clinical outcome compared with IV administration.
Journal of Interventional Cardiology 03/2012; 25(3):223-34. · 1.18 Impact Factor
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ABSTRACT: Abstract Background Autologous epidermal transplantation is available for the treatment of stable vitiligo. But the results of this technique are affected by many factors. Objectives: It is important to investigate the long term results and factors that might influence the outcom of the autologous epidermal grafting technique in patients with vitiligo to form a basis for guidance for patients. Methods We studied a follow up study involving 173 patients (95male, 78 female)with vitiligo vulgaris and 109 patients (59 male, 50 female) with segmental vitiligo who underwent autologous epidermal grafting .We investigated the long term percentage of repigmentation and colour matching up to 13 years after treatment(mean 1.87 years).
Journal of Dermatological Treatment 03/2012; · 1.23 Impact Factor
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ABSTRACT: Previous studies indicate that oral supplementation with n-3 PUFA protects against atherosclerotic disease by inhibiting inflammatory processes, which underlie atherosclerosis and are reflected by the plasma concentrations of soluble adhesion molecules. However, consistent results were not obtained among studies.
The objective was to assess the effects of n-3 PUFA supplementation on plasma concentrations of soluble adhesion molecules.
We conducted a meta-analysis of randomized controlled trials identified from PubMed, Embase, the Cochrane Library, and reference lists of relevant articles and reviews.
Eighteen studies were included. n-3 PUFA supplementation reduced plasma concentrations of soluble intercellular adhesion molecule-1 [sICAM-1; weighted mean difference (WMD): -5.17; 95% CI: -10.07, -0.27; P = 0.04] but had no significant effects on soluble vascular cell adhesion molecule-1 (WMD: -5.90; 95% CI: -17.63, 5.84; P = 0.32), soluble P-selectin (WMD: -1.53; 95% CI: -4.33, 1.28; P = 0.29), or soluble E-selectin (WMD: 0.46; 95% CI: -1.54, 2.46; P = 0.65). Subgroup analysis stratified by the subjects' health status showed that n-3 PUFA supplementation reduced sICAM-1 concentrations in healthy subjects (WMD: -8.87; 95% CI: -15.20, -2.53; P = 0.006; heterogeneity test: I² = 0%, P = 0.76) and in subjects with dyslipidemia (WMD: -15.31; 95% CI: -26.82, -3.81; P = 0.009; heterogeneity test: I² = 26%, P = 0.26).
n-3 PUFA supplementation can reduce plasma concentrations of sICAM-1. The effect is identified in both healthy subjects and subjects with dyslipidemia, which supports the hypothesis that n-3 PUFA can be supplemented as a primary or secondary means for preventing the development as well as the progression of atherosclerosis.
American Journal of Clinical Nutrition 02/2012; 95(4):972-80. · 6.67 Impact Factor
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ABSTRACT: The polymorphisms of angiotensin-converting enzyme 2 (ACE2) gene have been suggested to be linked to increase risk of essential hypertension in multiple populations. However, the results are still debatable. To assess the association between ACE2 G8970A genetic polymorphism and essential hypertension, we conducted a meta-analysis of case-control studies across different ethnicity. PubMed, Embase, CBM, Wanfang and VIP databases were searched, and a total of 11 separate studies in females and nine separate studies in males met the inclusion criteria. Because ACE2 is on the X chromosome, data for each sex were analyzed separately. The selected studies contained 7,251 (4,472 females/2,779 males) hypertensive patients and 3,800 (2,161 females/1,639 males) normotensive controls. A statistically significant association was observed between the G8970A gene polymorphism and essential hypertension risk in female hypertensive group in the recessive genetic model (AA vs. GG+GA: P = 0.03, OR = 1.15, 95% CI = 1.02-1.30, P(heterogeneity) = 0.40, I(2) = 5%, fixed-effects model). Although no association was shown between the frequency of the A allele and the genetic susceptibility to essential hypertension in all male patients (A Allele: P = 0.38, OR = 1.10, 95% CI = 0.89-1.38, P(heterogeneity) = 0.02, I(2) = 56%, random-effects model), we found that the relationship between carrier of A allele and the essential hypertension risk in Han-Chinese male patients subgroup (A Allele: P = 0.006, OR = 1.21, 95% CI = 1.06–1.38, P(heterogeneity) = 0.10, I(2) = 44%, fixed-effects model). The current meta-analysis provided solid evidence suggesting that ACE2 gene polymorphism G8790A was probably a genetic risk factor for essential hypertension across different ethnic populations in female subjects and in Han-Chinese male subjects.
Molecular Biology Reports 02/2012; 39(6):6581-9. · 2.93 Impact Factor
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ABSTRACT: A tightly regulated catabolic process named autophagy involves the degradation of intracellular components via lysosomes. Here we investigate the antitumor effect of E Platinum, a newly synthesized derivative of oxaliplatin, in vivo and in vitro. E Platinum exhibits growth inhibition of various tumor cells in a dose-dependent manner, but the mechanism underlying it is unclear. Based on theory introducing autophagy, we preliminarily investigate whether autophagy could contribute to the antitumor activity of E Platinum. Our results showed that autophagy induced by 12.5 μM E Platinum in gastric carcinoma BGC-823 cells was significantly characterized by the FITC-fluorescent microtubule associated protein 1 light chain 3 (MAP-LC3), lysosomal-rich/acidic compartments visualized with Lysotracker red (LTR-red) and an accumulation of numerous large autophagic vesicles within the cytoplasm, but not in the control cells. Meanwhile treatment of cells with 12.5 μM E Platinum resulted in conversion of water soluble LC3 (LC3-I) to lipidated and autophagosome-associated form (LC3-II) as well as increasing expression of autophagy protein Beclin 1. Activation of predominant lysosomal aspartic protease, LAMP-1 and cathepsin D, was demonstrated. Moreover, RNA interference targeting Beclin 1, inhibition of autophagy by 3-methyladenine (3-MA) and chloroquine significantly suppressed the above process as well as the BGC-823 cells growth inhibition triggered by 12.5 μM E Platinum. Studies of mechanism revealed that E Platinum suppressed activation of mTOR and p70S6K by decreasing phosphorylation of Akt, ERK1/2, JNK and p38 involved in mitogen-activated protein kinase signaling. We supported new evidences for E Platinum as a promising antitumor agent, involving with autophagy induction.
Toxicology Letters 01/2012; 210(1):78-86. · 3.23 Impact Factor
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Na Wu,
Yuanyuan Zhang,
Jun Fu,
Ruifen Zhang,
Lan Feng,
Yongfei Hu,
Xiaoliang Li, Na Lu,
Xiuqin Zhao,
Yuanlong Pan,
Jing Li,
Baoli Zhu,
Kanglin Wan
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ABSTRACT: A novel two-step multiple displacement amplification-PCR (MDA-PCR) assay for tuberculosis detection in 200 sputum specimens was evaluated. The MDA-PCR assay indicated a significant increase in sensitivity and specificity compared with those of standard PCR alone.
Journal of clinical microbiology 01/2012; 50(4):1443-5. · 4.16 Impact Factor
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ABSTRACT: Helical tomotherapy (HT) is a new image-guided intensity-modulated radiation therapy (IMRT). The aim of this study was to evaluate the changes in the target volume and organs at risk (OARs) of patients with nasopharyngeal carcinoma (NPC) during helical tomotherapy.
Forty-three patients with NPC and treated via HT from March 2008 to January 2010 were reviewed retrospectively. Repeated CT scanning and plan adaptation were conducted at the 20th fraction during radiotherapy. The volumetric differences between the two scans were evaluated for nasopharyngeal tumor and retro-pharyngeal lymph nodes (GTVnx), neck lymph nodes (GTVnd), and parotid glands, as well as the axial diameter of the head.
The median interval between the two scans was 25 days (23 - 28 days). The volumetric decrease in GTVnx was 30.1% (median, 29.8%) and in GTVnd 41.6% (median, 45.9%). The variation in the GTVnd volume was correlated with the weight loss of the patient. The volume of the left parotid gland decreased by 35.5% (median, 33.4%) and of the right parotid glands decreased by 36.8% (median, 33.5%). The axial diameter of the head decreased by 9.39% (median, 9.1%).
The target volume and OARs of patients with NPC varied considerably during HT. These changes may have potential dosimetric effects on the target volume and/or OARs and influence the clinical outcome. Repeated CT scanning and replanning during the HT for NPC patients with a large target volume or an obvious weight loss are recommended.
Chinese medical journal 01/2012; 125(1):87-90. · 0.86 Impact Factor
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Yuanlong Pan,
Xi Yang,
Jia Duan, Na Lu,
Andrea S Leung,
Vanessa Tran,
Yongfei Hu,
Na Wu,
Di Liu,
Zhiming Wang,
Xuping Yu,
Chen Chen,
Yuanyuan Zhang,
Kanglin Wan,
Jun Liu,
Baoli Zhu
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ABSTRACT: Mycobacterium bovis Bacille Calmette-Guérin (BCG) is the only vaccine available against tuberculosis (TB). A number of BCG strains are in use, and they exhibit biochemical and genetic differences. We report the genome sequences of four BCG strains representing different lineages, which will help to design more effective TB vaccines.
Journal of bacteriology 06/2011; 193(12):3152-3. · 3.94 Impact Factor
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Zuowei Wu,
Ming Li,
Changjun Wang,
Jing Li, Na Lu,
Ruifen Zhang,
Yongqiang Jiang,
Ruifu Yang,
Cuihua Liu,
Hui Liao,
George F Gao,
Jiaqi Tang,
Baoli Zhu
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ABSTRACT: Our previous studies revealed that a new disease form of streptococcal toxic shock syndrome (STSS) is associated with specific Streptococcus suis serotype 2 (SS2) strains. To achieve a better understanding of the pathogenicity and evolution of SS2 at the whole-genome level, comparative genomic analysis of 18 SS2 strains, selected on the basis of virulence and geographic origin, was performed using NimbleGen tiling arrays.
Our results demonstrate that SS2 isolates have highly divergent genomes. The 89K pathogenicity island (PAI), which has been previously recognized as unique to the Chinese epidemic strains causing STSS, was partially included in some other virulent and avirulent strains. The ABC-type transport systems, encoded by 89K, were hypothesized to greatly contribute to the catastrophic features of STSS. Moreover, we identified many polymorphisms in genes encoding candidate or known virulence factors, such as PlcR, lipase, sortases, the pilus-associated proteins, and the response regulator RevS and CtsR. On the basis of analysis of regions of differences (RDs) across the entire genome for the 18 selected SS2 strains, a model of microevolution for these strains is proposed, which provides clues into Streptococcus pathogenicity and evolution.
Our deep comparative genomic analysis of the 89K PAI present in the genome of SS2 strains revealed details into how some virulent strains acquired genes that may contribute to STSS, which may lead to better environmental monitoring of epidemic SS2 strains.
BMC Genomics 01/2011; 12:219. · 4.07 Impact Factor
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Yongfei Hu,
Chengzhang Fu,
Yunpeng Huang,
Yeshi Yin,
Gong Cheng,
Fang Lei, Na Lu,
Jing Li,
Elizabeth Jane Ashforth,
Lixin Zhang,
Baoli Zhu
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ABSTRACT: Metagenomic cloning is a powerful tool for the discovery of novel genes and biocatalysts from environmental microorganisms. Based on activity screening of a marine sediment microbial metagenomic library, a total of 19 fosmid clones showing lipolytic activity were identified. After subcloning, 15 different lipolytic genes were obtained; their encoded proteins showed 32-68% amino acid identity with proteins in the database. Multiple sequence alignment and phylogenetic tree analysis demonstrated that most of these predicted proteins are new members of known families of bacterial lipolytic enzymes. However, two proteins, FLS18C and FLS18D, could not be assigned to any known family, thus probably representing a novel family of the bacterial lipolytic enzyme. The activity assay results indicated that most of these lipolytic enzymes showed optimum temperature for hydrolysis at 40-50 degrees C with p-nitrophenol butyrate as a substrate. The lipolytic gene fls18D was overexpressed, and the resulting protein FLS18D was characterized as an alkaline esterase. Furthermore, the whole sequence of fosmid pFL18 containing FLS18C and FLS18D was shotgun sequenced, and a total of 26 ORFs on it were analyzed and annotated.
FEMS Microbiology Ecology 02/2010; 72(2):228-37. · 3.41 Impact Factor
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ABSTRACT: Highly ordered boron-doped TiO2 nanotube arrays were fabricated via a facile electrodeposition method. X-ray photoelectron spectroscopy (XPS) analysis revealed incorporated B atoms in the lattice of a TiO2 nanotube array. The X-ray diffraction (XRD) spectrum indicated improved crystallinity of boron-doped TiO2 nanotube arrays, relative to undoped TiO2 nanotube arrays. A shift of the absorption edge toward the visible region and a new absorption shoulder (380–510 nm) of boron-doped TiO2 nanotube arrays were observed via diffuse reflectance spectroscopy (DRS). In photoelectrochemical measurements, under either ultraviolet (UV) or visible-light irradiation, the photocurrent conversion efficiency was enhanced because of boron doping. The photoelectrocatalysis of phenol under simulated solar irradiation was performed using boron-doped or undoped TiO2 nanotube arrays, and the kinetic constant of a boron-doped TiO2 nanotube array photoelectrode was increased by ca. 28%, compared to that of an undoped TiO2 nanotube array photoelectrode.
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