Kulkarni T.S.,Biotechnology |
Villagomez R.,National Center for Ecological Analysis And Synthesis |
Mahmood T.,Biotechnology |
Logan D.T.,Biochemistry and Structural Biology |
And 2 more authors.
Proteins: Structure, Function and Bioinformatics | Year: 2017
The β-glucosidase TnBgl1A catalyses hydrolysis of O-linked terminal β-glycosidic bonds at the nonreducing end of glycosides/oligosaccharides. Enzymes with this specificity have potential in lignocellulose conversion (degrading cellobiose to glucose) and conversion of bioactive flavonoids (modification of glycosylation results in modulation of bioavailability). Previous work has shown TnBgl1A to hydrolyse 3, 4′ and 7 glucosylation in flavonoids, and although conversion of 3-glucosylated substrate to aglycone was low, it was improved by mutagenesis of residue N220. To further explore structure-function relationships, the crystal structure of the nucleophile mutant TnBgl1A-E349G was determined at 1.9 Å resolution, and docking studies of flavonoid substrates were made to reveal substrate interacting residues. A series of single amino acid changes were introduced in the aglycone binding region [N220(S/F), N221(S/F), F224(I), F310(L/E), and W322(A)] of the wild type. Activity screening was made on eight glucosylated flavonoids, and kinetic parameters were monitored for the flavonoid quercetin-3-glucoside (Q3), as well as for the model substrate para-nitrophenyl-β-d-glucopyranoside (pNPGlc). Substitution by Ser at N220 or N221 increased the catalytic efficiency on both pNPGlc and Q3. Residue W322 was proven important for substrate accomodation, as mutagenesis to W322A resulted in a large reduction of hydrolytic activity on 3-glucosylated flavonoids. Flavonoid glucoside hydrolysis was unaffected by mutations at positions 224 and 310. The mutations did not significantly affect thermal stability, and the variants kept an apparent unfolding temperature of 101°C. This work pinpoints positions in the aglycone region of TnBgl1A of importance for specificity on flavonoid-3-glucosides, improving the molecular understanding of activity in GH1 enzymes. © 2017 Wiley Periodicals, Inc.
Mefteh F.B.,University of Sfax |
Daoud A.,University of Sfax |
Bouket A.C.,Biotechnology |
Bouket A.C.,Osaka Prefecture University |
And 9 more authors.
Frontiers in Microbiology | Year: 2017
In this study, we aimed to explore and compare the composition, metabolic diversity and antimicrobial potential of endophytic fungi colonizing internal tissues of healthy and brittle leaf diseased (BLD) date palm trees (Phoenix dactylifera L.) widely cultivated in arid zones of Tunisia. A total of 52 endophytic fungi were isolated from healthy and BLD roots of date palm trees, identified based on internal transcribed spacer-rDNA sequence analysis and shown to represent 13 species belonging to five genera. About 36.8% of isolates were shared between healthy and diseased root fungal microbiomes, whereas 18.4 and 44.7% of isolates were specific to healthy and BLD root fungal microbiomes, respectively. All isolates were able to produce at least two of the screened enzymes including amylase, cellulase, chitinase, pectinase, protease, laccase and lipase. A preliminary screening of the isolates using disk diffusion method for antibacterial activity against four Gram-positive and three Gram-negative bacteria and antifungal activities against three phytopathogenic fungi indicated that healthy and BLD root fungal microbiomes displayed interesting bioactivities against examined bacteria and broad spectrum bioactivity against fungal pathogens. Some of these endophytic fungi (17 isolates) were fermented and their extracts were evaluated for antimicrobial potential against bacterial and fungal isolates. Results revealed that fungal extracts exhibited antibacterial activities and were responsible for approximately half of antifungal activities against living fungi. These results suggest a strong link between fungal bioactivities and their secondary metabolite arsenal. EtOAc extracts of Geotrichum candidum and Thielaviopsis punctulata originating from BLD microbiome gave best results against Micrococcus luteus and Bacillus subtilis with minimum inhibitory concentration (MIC, 0.78 mg/mL) and minimum bactericidal concentration (6.25 mg/mL). G. candidum gave the best result against Rhizoctonia solani with MIC 0.78 mg/mL and minimum fungicidal concentration (MFC, 6.25 mg/mL). In conclusion, using plant microbiomes subjected to biotic stresses offers new endophytes with different bioactivities than those of healthy plants. Therefore, date palm endophytic fungi represent a hidden untapped arsenal of antibacterial and broad spectrum antifungal secondary metabolites and could be considered promising source of bioactive compounds with industrial and pharmaceutical applications. © 2017 Mefteh, Daoud, Chenari Bouket, Alenezi, Luptakova, Rateb, Kadri, Gharsallah and Belbahri.
Ara K.Z.G.,Biotechnology |
Lundemo P.,Matis |
Fridjonsson O.H.,University of Iceland |
Hreggvidsson G.O.,University of Iceland |
And 2 more authors.
Glycobiology | Year: 2015
Cyclodextrin glucanotransferases (CGTases; EC 126.96.36.199) have mainly been characterized for their ability to produce cyclodextrins (CDs) from starch in an intramolecular transglycosylation reaction (cyclization). However, this class of enzymes can also catalyze intermolecular transglycosylation via disproportionation or coupling reactions onto a wide array of acceptors and could therefore be valuable as a tool for glycosylation. In this paper, we report the gene isolation, via the CODEHOP strategy, expression and characterization of a novel CGTase (CspCGT13) from a Carboxydocella sp. This enzyme is the first glycoside hydrolase isolated from the genus, indicating starch degradation via cyclodextrin production in the Carboxydocella strain. The fundamental reactivities of this novel CGTase are characterized and compared with two commercial CGTases, assayed under identical condition, in order to facilitate interpretation of the results. The comparison showed that the enzyme, CspCGT13, displayed high coupling activity using γ-CD as donor, despite preferentially forming α- and β-CD in the cyclization reaction using wheat starch as substrate. Comparison of subsite conservation within previously characterized CGTases showed significant sequence variation in sub-sites -3 and -7, which may be important for the coupling activity. © The Author 2014.
Pinheiro K.S.,Tiradentes University |
Pinheiro K.S.,Laboratory of Morphology and Structural Biology |
Ribeiro D.R.,Industrial Biotechnology |
Ribeiro D.R.,Laboratory of Morphology and Structural Biology |
And 12 more authors.
Acta Cirurgica Brasileira | Year: 2014
PURPOSE: To evaluate modulatory effects of a hydroalcoholic extract of Brazilian red propolis (HERP) on dermal carcinogenesis using a murine model. METHODS: The HERP was used at concentrations of 10, 50 and 100 mg/kg (PROP10, PROP50 and PROP100, respectively) to modulate dermal carcinogenesis induced by the application of 9,10-dimetil-1,2-benzatraceno (DMBA) on the backs of animals. RESULTS: The chemical compounds identified in HERP included propyl gallate, catechin, epicatechin and formononetin. PROP100 treatment resulted in significantly decreased tumor multiplicity throughout the five weeks of tumor promotion (p<0.05), and this concentration also resulted in the highest frequency of verrucous tumors (p<0.05). All of the tumors that developed in DMBA-treated animals were regarded as squamous cell carcinomas and were either diagnosed as non-invasive verrucous carcinomas or invasive squamous cell carcinomas (SCCs). The average score for malignancy was significantly lower in the PROP100-treated group than the non-treated group (p<0.05), but there was no difference between the other groups (p>0.05). CONCLUSION: The oral administration of hydroalcoholic extract of Brazilian red propolis at a dose of 100 mg/kg had a significant modulatory effect on the formation, differentiation and progression of chemically induced squamous cell carcinoma in a murine experimental model.
PubMed | University of Iceland, Biotechnology and Matis
Type: Journal Article | Journal: Glycobiology | Year: 2015
Cyclodextrin glucanotransferases (CGTases; EC 188.8.131.52) have mainly been characterized for their ability to produce cyclodextrins (CDs) from starch in an intramolecular transglycosylation reaction (cyclization). However, this class of enzymes can also catalyze intermolecular transglycosylation via disproportionation or coupling reactions onto a wide array of acceptors and could therefore be valuable as a tool for glycosylation.In this paper, we report the gene isolation, via the CODEHOP strategy, expression and characterization of a novel CGTase (CspCGT13) from a Carboxydocella sp. This enzyme is the first glycoside hydrolase isolated from the genus, indicating starch degradation via cyclodextrin production in the Carboxydocella strain. The fundamental reactivities of this novel CGTase are characterized and compared with two commercial CGTases, assayed under identical condition, in order to facilitate interpretation of the results. The comparison showed that the enzyme, CspCGT13, displayed high coupling activity using -CD as donor, despite preferentially forming - and -CD in the cyclization reaction using wheat starch as substrate. Comparison of subsite conservation within previously characterized CGTases showed significant sequence variation in subsites -3 and -7, which may be important for the coupling activity.
PubMed | Biotechnology, Autonomous University of Mexico City, Biotechnology Program and Human Acupuncture Program
Type: Journal Article | Journal: Journal of research in medical sciences : the official journal of Isfahan University of Medical Sciences | Year: 2014
Obesity is a major health problem worldwide for which conventional therapy efficacy is limited. Traditional Chinese medicine, particularly body acupoint stimulation, provides an alternative, effective, and safe therapy for this medical challenge. The present study was designed to compare the effects of distinct methods to stimulate the same set of acupoints, on anthropometric and biochemical parameters in obese women.Ninety-nine obese women were randomly assigned to six groups of treatment: Acupuncture with moxibustion, long needle acupuncture with moxibustion, electroacupuncture (EA), EA with moxibustion, embedded catgut with moxibustion (CGM) and sham acupuncture as control. Obesity-related parameters, including body weight, body mass index (BMI), waist and hip circumferences, waist/hip ratio, biochemical parameters (triglycerides, cholesterol, glucose, insulin) and homeostasis model of assessment - insulin resistance (HOMA-IR) index, were determined before and after each treatment.Body weight and BMI were significantly reduced in response to all treatments. Interestingly, acupoint catgut embedding therapy combined with moxibustion was the only treatment that produced a significant reduction in body weight (3.1 0.2 kg, P < 0.001), BMI (1.3 0.1 kg/m(2), P < 0.001), insulin (3.5 0.8 mcU/ml, P < 0.1) and HOMA-IR (1.4 0.2 units, P < 0.01) in comparison with sham group. Furthermore, this treatment was able to bring back obese women to a state of insulin sensitivity, indicating that acupoint catgut embedding therapy combined with moxibustion could be useful as a complementary therapy to reduce the risk of diabetes associated to obesity in women.Overall, our results confirmed the effectiveness of acupoints stimulation to assist in the control of body weight in women. They also highlighted the more favorable effects of embedded catgut-moxibustion combination that may be due to the extended and consistent stimulation of acupoints.
PubMed | Applied Microbiology and Biotechnology, Medical Laboratory Technology, Vindico NanoBioTechnology Inc., Medicity and Biotechnology
Type: Journal Article | Journal: Indian journal of hematology & blood transfusion : an official journal of Indian Society of Hematology and Blood Transfusion | Year: 2015
With an increase in the number of transplants happening globally, hematopoietic stem cells (HSC) transplantation from matched unrelated donor (MUD) has begun. The increasing trend of MUD transplants across countries has been largely facilitated with the conspicuous growth of volunteer HSC donor noted in the last decade i.e. 8 million HSC donors in 2002 to more than 22 million in 2013 registered in 71 member registries of the Bone Marrow Donor Worldwide (BMDW). Some populations of the world are still very poorly represented in these registries. Since, the chances of successful engraftment and disease free survival are directly proportional to the HLA compatibility between the recipient and the prospective donor, the diversity of the HLA system at the antigenic and allelic level and the heterogeneity of HLA data of the registered donors has a bearing on the probability of finding a volunteer unrelated HSC donor for patients from such populations. In the present study 126 patients were identified suffering from hematological diseases requiring MUD transplant. Their HLA typing was performed and search was done using BMDW database. The search results for these Indian patients in the multinational registry as well as in the Indian Registries were analyzed using mean, range, standard deviation and finally evaluated in terms of probability for finding matched donor (MUD). Total Asian population is only 11% in the BMDW making it difficult to find a MUD for an Asian patient. The current study supports this, experimentally; revealing that the probability of finding an allele match for an Indian patient in the multinational Human Leukocyte Antigen (HLA) registries is 16% and a dismal 0.008% in the Indian registries (donors in Indian registries is just 33,678 as compared to 22.5 million in BMDW). This greatly, emphasizes on enhancing the number of Indian donors in Indian and multi-national registries.
Xie J.,China Agricultural University |
Zhang S.,China Agricultural University |
Hu Y.,China Agricultural University |
Li D.,China Agricultural University |
And 9 more authors.
Biochimica et Biophysica Acta - Molecular Basis of Disease | Year: 2014
The cytokine storm which is a great burden on humanity in highly pathogenic influenza virus infections requires activation of multiple signaling pathways. These pathways, such as MAPK and JNK, are important for viral replication and host inflammatory response. Here we examined the roles of JNK downstream molecule c-jun in host inflammatory responses and H5N1 virus replication using a c-jun targeted DNAzyme (Dz13). Transfection of Dz13 significantly reduced H5N1 influenza virus replication in human lung epithelial cells. Concomitantly, there was a decreased expression of pro-inflammatory cytokines (tumor necrosis factor (TNF)-α, interferon (IFN)-β and interleukin (IL)-6) in c-jun suppressed cells, while the expression of anti-inflammatory cytokines, such as IL-10, was increased. In vivo, compared with control groups, suppression of c-jun improved the survival rate of mice infected with H5N1 virus (55.5% in Dz13 treated mice versus ≤11% of control mice) and decreased the CD8+ T cell proliferation. Simultaneously, the pulmonary inflammatory response and viral burden also decreased in the Dz13 treated group. Thus, our data demonstrated a critical role for c-jun in the establishment of H5N1 infection and subsequent inflammatory reactions, which suggest that c-jun may be a potential therapeutic target for viral pneumonia. © 2014.
Lopez-Cuellar M.R.,CINVESTAV |
Alba-Flores J.,CINVESTAV |
Rodriguez J.N.G.,Biotechnology |
International Journal of Biological Macromolecules | Year: 2011
Wautersia eutropha was able to synthesize medium chain length polyhydroxyalkanoates (PHAs) when canola oil was used as carbon source. W. eutropha was cultivated using fructose and ammonium sulphate as carbon and nitrogen sources, respectively, for growth and inoculum development. The experiments were done in a laboratory scale bioreactor in three stages. Initially, the biomass was adapted in a batch culture. Secondly, a fed-batch was used to increase the cell dry weight and PHA concentration to 4.36gL-1 and 0.36gL-1, respectively. Finally, after the addition of canola oil as carbon source a final concentration of 18.27gL-1 PHA was obtained after 40h of fermentation. With canola oil as carbon source, the polymer content of the cell dry matter was 90%. The polymer was purified from dried cells and analyzed by FTIR, NMR and DSC using PHB as reference. The polymer produced by W. eutropha from canola oil had four carbon monomers in the structure of the PHA and identified by 1H and 13C NMR analysis as 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), 3-hydroxyoctanoate (3HO), and 3-hydroxydodecanoate (3HDD). © 2010 Elsevier B.V.
Ramkumar G.,Biotechnology |
Madhav M.S.,Biotechnology |
Rama Devi S.J.S.,Biotechnology |
Manimaran P.,Biotechnology |
And 5 more authors.
Gene | Year: 2014
Improvement of host plant resistance is one of the best methods to protect the yield from biotic stresses. Incorporation of major resistance genes or their variants into elite rice varieties will enhance the host plant resistance and its durability. Allele mining is a preferred choice to discover the novel allelic variants of major genes from wide range of germplasm. 'True' allele mining includes coding and noncoding regions, which are known to affect the plant phenotype, eventually. In this study, major blast resistance gene, Pita was analyzed by allele and promoter mining strategy and its different allelic variants were discovered from landraces and wild Oryza species. Polymorphisms at allelic sequences as well as transcription factor binding motif (TFBM) level were examined. At motif level, MYB1AT is present in PitaTadukan and other resistance alleles, but was absent in the susceptible allele. Core promoter was demarked with 449bp, employing serial promoter deletion strategy. Promoter with 1592bp upstream region could express the gfp two fold higher than the core promoter. The identified Pita resistance allele (PitaKonibora) can be directly used in rice blast resistance breeding programs. Moreover, characterization of Pita core promoter led to deeper understanding of resistance gene's regulation and the identified core promoter can be utilized to express similar genes in rice. © 2014 Elsevier B.V.