PHYTOCHEMICALS AS POTENTIAL INHIBITORS OF LANOSTEROL 14 Α-DEMETHYLASE (CYP51) ENZYME: AN IN SILICO STUDY ON SIXTY MOLECULES

Lanosterol 14 α-demethylase (CYP51) is a key protein involved in ergosterol biosynthesis of Candida albicans and a crucial target for ergosterol synthesis inhibition. However, in the last two decades drug resistance is reported under clinical situations to most of the prescribed antifungal drugs like azole group of drugs. In this study, molecular docking of sixty plant molecules with Lanosterol 14 α-demethylase protein has been done. The homology modeling tool PHYRE2 was used to predict the structure of Lanosterol 14 α-demethylase. Predicted structure was used for docking studies with sixty plant molecules by using Autodock 1.5.6 cr2™. Among the sixty plant molecules, forty-seven were found to form hydrogen bond and the rest of the plant molecules did not form a hydrogen bond with Lanosterol 14 α-demethylase. Docking study of a library of sixty molecules revealed that 48 plant molecules showed an excellent and good binding affinity with predicted protein model Lanosterol 14 α-demethylase of Candida albicans. The binding residue comparison of docked molecules with that of Ketoconazole revealed, fourteen molecules have similar binding residue. These fourteen molecules may have a similar mode of action as that of Ketoconazole. These molecules should be screened and used to discover new antifungal therapeutic drugs

MEDICINAL MUSHROOM BIOACTIVES: POTENTIAL SOURCES FOR ANTI-CANCER DRUG DEVELOPMENT

Mushrooms represent a major yet largely untapped source of therapeutically useful bioactive compounds. Despite mushrooms were in use since antiquity in traditional folk medicine attempts to isolate their bioactive components and to elucidate their medicinal properties have started only recently. Many pharmaceutical substances with unique properties were recently extracted from mushrooms and made their way all over the world. A number of medicinal mushrooms have been identified to possess anticancer effects recently. Some of the well-known examples are Lentinan from Lentinus edodes, Krestin from Trametes versicolor, Ganopoly from Ganoderma lucidum and Schizophyllan from Schizophyllum commune. We investigated the anticancer activities of a number of medicinal mushrooms in our laboratory. Some of the recent scientific evdences on the anticancer activities of Ganoderma lucidum, Phellinus rimosus, and Fomitopsis pinicola are discussed in this short review

Comparative analysis of expressed sequence tags (ESTs) between drought-tolerant and -susceptible genotypes of chickpea under terminal drought stress

<p>Abstract</p> <p>Background</p> <p>Chickpea (<it>Cicer arietinum </it>L.) is an important grain-legume crop that is mainly grown in rainfed areas, where terminal drought is a major constraint to its productivity. We generated expressed sequence tags (ESTs) by suppression subtraction hybridization (SSH) to identify differentially expressed genes in drought-tolerant and -susceptible genotypes in chickpea.</p> <p>Results</p> <p>EST libraries were generated by SSH from root and shoot tissues of IC4958 (drought tolerant) and ICC 1882 (drought resistant) exposed to terminal drought conditions by the dry down method. SSH libraries were also constructed by using 2 sets of bulks prepared from the RNA of root tissues from selected recombinant inbred lines (RILs) (10 each) for the extreme high and low root biomass phenotype. A total of 3062 unigenes (638 contigs and 2424 singletons), 51.4% of which were novel in chickpea, were derived by cluster assembly and sequence alignment of 5949 ESTs. Only 2185 (71%) unigenes showed significant BLASTX similarity (<1E-06) in the NCBI non-redundant (nr) database. Gene ontology functional classification terms (BLASTX results and GO term), were retrieved for 2006 (92.0%) sequences, and 656 sequences were further annotated with 812 Enzyme Commission (EC) codes and were mapped to 108 different KEGG pathways. In addition, expression status of 830 unigenes in response to terminal drought stress was evaluated using macro-array (dot blots). The expression of few selected genes was validated by northern blotting and quantitative real-time PCR assay.</p> <p>Conclusion</p> <p>Our study compares not only genes that are up- and down-regulated in a drought-tolerant genotype under terminal drought stress and a drought susceptible genotype but also between the bulks of the selected RILs exhibiting extreme phenotypes. More than 50% of the genes identified have been shown to be associated with drought stress in chickpea for the first time. This study not only serves as resource for marker discovery, but can provide a better insight into the selection of candidate genes (both up- and downregulated) associated with drought tolerance. These results can be used to identify suitable targets for manipulating the drought-tolerance trait in chickpea.</p

The CarERF genes in chickpea (Cicer arietinum L.) and the identification of CarERF116 as abiotic stress responsive transcription factor

The AP2/ERF family is one of the largest transcription factor gene families that are involved in various plant processes, especially in response to biotic and abiotic stresses. Complete genome sequences of one of the world's most important pulse crops chickpea (Cicer arietinum L.), has provided an important opportunity to identify and characterize genome-wide ERF genes. In this study, we identified 120 putative ERF genes from chickpea. The genomic organization of the chickpea ERF genes suggested that the gene family might have been expanded through the segmental duplications. The 120 member ERF family was classified into eleven distinct groups (I-X and VI-L). Transcriptional factor CarERF116, which is differentially expressed between drought tolerant and susceptible chickpea cultivar under terminal drought stress has been identified and functionally characterized. The CarERF116 encodes a putative protein of 241 amino acids and classified into group IX of ERF family. An in vitro CarERF116 protein-DNA binding assay demonstrated that CarERF116 protein specifically interacts with GCC box. We demonstrate that CarERF116 is capable of transactivation activity of and show that the functional transcriptional domain lies at the C-terminal region of the CarERF116. In transgenic Arabidopsis plants overexpressing CarERF116, significant up-regulation of several stress related genes were observed. These plants also exhibit resistance to osmotic stress and reduced sensitivity to ABA during seed germination. Based on these findings, we conclude that CarERF116 is an abiotic stress responsive gene, which plays an important role in stress tolerance. In addition, the present study leads to genome-wide identification and evolutionary analyses of chickpea ERF gene family, which will facilitate further research on this important group of genes and provides valuable resources for comparative genomics among the grain legumes

Evolution of CDC42, a putative virulence factor triggering meristematic growth in black yeasts

The cell division cycle gene (CDC42) controlling cellular polarization was studied in members of Chaetothyriales. Based on ribosomal genes, ancestral members of the order exhibit meristematic growth in view of their colonization of inert surfaces such as rock, whereas in derived members of the order the gene is a putative virulence factor involved in expression of the muriform cell, the invasive phase in human chromoblastomycosis. Specific primers were developed to amplify a portion of the gene of 32 members of the order with known position according to ribosomal phylogeny. Phylogeny of CDC42 proved to be very different. In all members of Chaetohyriales the protein sequence is highly conserved. In most species, distributed all over the phylogenetic tree, introns and 3rd codon positions are also invariant. However, a number of species had paralogues with considerable deviation in non-coding exon positions, and synchronous variation in introns, although non-synonomous variation had remained very limited. In some strains both orthologues and paralogues were present. It is concluded that CDC42 does not show any orthologous evolution, and that its paralogues haves the same function but are structurally relaxed. The variation or absence thereof could not be linked to ecological changes, from rock-inhabiting to pathogenic life style. It is concluded that eventual pathogenicity in Chaetothyriales is not expressed at the DNA level in CDC42 evolution

Efficacy of some medicinal plants against human dental pathogens

123-127Dental caries is one of the most prevalent diseases having multifactorial etiology. Most of the treatments in dental caries is aimed at either elimination or suppression of bacteria by antibiotics. Increased resistance of oral bacteria to antibiotics however, has developed keen interest of researcher in herbal treatment. In our investigation we have screened nine medicinal plants from Marathwada region. We have proved effective inhibition of dental pathogens by aqueous extract of plants. Amongst selected plants leaves of Emblica officinalis Gaertn. syn. Phyllanthus emblica Linn. and Terminalia bellirica Roxb. and flowers of Syzygium aromaticum (Linn.) Merrill &amp; Perry showed three to four times more inhibition in comparison with effective antibiotics like Carbenicillin, Tetracycline, Nalidixic acid and Nitrofurantoin of four dental pathogens, viz. Streptococcus mutans, Streptococcus mitis, Streptococcus sanguis and Actinobacillus actinomycetemcomitans isolated by us. </span

Sensitization of <it>Candida albicans</it> biofilms to various antifungal drugs by cyclosporine A

<p>Abstract</p> <p>Background</p> <p>Biofilms formed by <it>Candida albicans</it> are resistant towards most of the available antifungal drugs. Therefore, infections associated with <it>Candida</it> biofilms are considered as a threat to immunocompromised patients. Combinatorial drug therapy may be a good strategy to combat <it>C. albicans</it> biofilms.</p> <p>Methods</p> <p>Combinations of five antifungal drugs- fluconazole (FLC), voriconazole (VOR), caspofungin (CSP), amphotericin B (AmB) and nystatin (NYT) with cyclosporine A (CSA) were tested <it>in vitro</it> against planktonic and biofilm growth of <it>C. albicans</it>. Standard broth micro dilution method was used to study planktonic growth, while biofilms were studied in an <it>in vitro</it> biofilm model. A chequerboard format was used to determine fractional inhibitory concentration indices (FICI) of combination effects. Biofilm growth was analyzed using XTT-metabolic assay.</p> <p>Results</p> <p>MICs of various antifungal drugs for planktonic growth of <it>C. albicans</it> were lowered in combination with CSA by 2 to 16 fold. Activity against biofilm development with FIC indices of 0.26, 0.28, 0.31 and 0.25 indicated synergistic interactions between FLC-CSA, VOR-CSA, CSP-CSA and AmB-CSA, respectively. Increase in efficacy of the drugs FLC, VOR and CSP against mature biofilms after addition of 62.5 μg/ml of CSA was evident with FIC indices 0.06, 0.14 and 0.37, respectively.</p> <p>Conclusions</p> <p>The combinations with CSA re<it>s</it>ulted in increased susceptibility of biofilms to antifungal drugs. Combination of antifungal drugs with CSA would be an effective prophylactic and therapeutic strategy against biofilm associated <it>C. albicans</it> infections.</p