Precision of age determination from otoliths,opercular bones,scales and vertebrae in the threatened freshwater snakehead,Channa punctata (Bloch, 1793)

Ages were estimated from otoliths, opercular bones, scales, and vertebrae of 514 specimens of Channa punctata from three Indian rivers – the Ganga, Gomti, and Yamuna – to evaluate the potential bias of age estimates between readers and between pairs of aging structures. Standard procedures were followed to prepare and study the age structures. Among all structures, otoliths showed highest (97.4%) values of agreement between readers' age estimates followed by the opercular bones (89.5%), scales (84.2%) and vertebrae (78.9%). Because of the highest percentage of agreement and lowest average percentage of error (0.05%) and coefficient of variation (0.76%) values between readers, otoliths were considered the most suitable aging structure for C. punctata. When otoliths ages were compared with those of the other structures viz., opercular bones, scales and vertebrae, percentage of agreement was found highest between estimates (90.8%) of otoliths and opercular bones.     

Cloning,purification and characterization of a cellulase-free xylanase from <Emphasis Type="Italic">Geobacillus thermodenitrificans</Emphasis> AK53

Geobacillus thermodenitrificans AK53 xyl gene encoding xylanase was isolated, cloned and expressed in Escherichia coli. After purifying recombinant xylanase from G. thermodenitrificans AK53 (GthAK53Xyl) to homogeneity by ammonium sulfate precipitation and ion exchange chromatography, biochemical properties of the enzyme were determined. The kinetic studies for GthAK53Xyl showed K_M value to be 4.34 mg/mL (for D-xylose) and V_max value to be 2028.9 μmoles mg^–1 min^–1. The optimal temperature and pH for enzyme activity were found out to be 70°C and 5.0, respectively. The expressed protein showed the highest sequence similarity with the xylanases of G. thermodenitrificans JK1 (JN209933) and G. thermodenitrificans T-2 (EU599644). Metal cations Mg²⁺ and Mn²⁺ were found to be required for the enzyme activity, however, Co²⁺, Hg²⁺, Fe²⁺ and Cu²⁺ ions caused inhibitor effect on it. GthAK53Xyl had no cellulolytic activity and degraded xylan in an endo-fashion. The action of the enzyme on xylan from oat spelt produced xylobiose and xylopentose. The reported results are suggestive of a xylanase exhibiting desirable kinetics, stability parameters and metal resistance required for the efficient production of xylobiose at industrial scale.     

Identification,cDNA Cloning,and Characterization of Luteinizing Hormone Beta Subunit (lhb) Gene in Catla catla

Reproductive hormones play a significant role in the gonadal development and gametogenesis process of animals. In the present study luteinizing hormone beta, (lhb) subunit gene was cloned and characterized from the brain of Catla catla. The lhb full-length of cDNA sequence is 629 bp which consists of 43bp 5'-UTR (untranslated region) 447bp, ORF(open reading frame) and 139 bp of 3'-UTR respectively. The coding region of lhb gene encoded a peptide of 148 amino acids. The coding sequence of lhb gene consist of a single N-linked glycosylation site (NET) and 12 cysteine knot residues. Phylogenetic analysis of C. catla Lhβ deduced amino acid sequence showed high similarity with Carassius auratus followed by Gobiocypris rarus. 3D structure Lhβ protein comprises of five β-sheets and six coils/loops. The qPCR results revealed lhb mRNA is mainly expressed in the pituitary, ovary while moderate expression was observed in brain and testis. To best our knowledge, this is the first report on the identification, molecular characterization and structural information regarding luteinizing hormone in Indian major carp.     

Evaluation of carbon sources for the production of inulinase by Aspergillus niger A42 and its characterization

Bioprocess and Biosystems Engineering - Inulinases are used for the production of high-fructose syrup and fructooligosaccharides, and are widely utilized in food and pharmaceutical industries. In...     

Recent developments in bioreactor scale production of bacterial polyhydroxyalkanoates

Bioprocess and Biosystems Engineering - Polyhydroxyalkanoates (PHAs) are biological plastics that are sustainable alternative to synthetic ones. Numerous microorganisms have been identified as PHAs...     

Phragmites australis — a helophytic grass — can establish successful partnership with phenol-degrading bacteria in a floating treatment wetland

Helophytic plants contribute significantly in phytoremediation of a variety of pollutants due to their physiological or biochemical mechanisms. Phenol, which is reported to have negative/deleterious effects on plant metabolism at concentrations higher than 500 mg/L, remains hard to be removed from the environmental compartments using conventional phytoremediation procedures. The present study aims to investigate the feasibility of using P. australis (a helophytic grass) in combination with three bacterial strains namely Acinetobacter lwofii ACRH76, Bacillus cereus LORH97, and Pseudomonas sp. LCRH90, in a floating treatment wetland (FTW) for the removal of phenol from contaminated water. The strains were screened based on their phenol degrading and plant growth promoting activities. We found that inoculated bacteria were able to colonize in the roots and shoots of P. australis, suggesting their potential role in the successful removal of phenol from the contaminated water. Pseudomonas sp. LCRH90 dominated the bacterial community structure followed by A. lowfii ACRH76 and B. cereus LORH97. The removal rate was significantly high when compared with the individual partners, i.e., plants and bacteria separately. The plant biomass, which was drastically reduced in the presence of phenol, recovered significantly with the inoculation of bacterial consortia. Likewise, highest reduction in chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total organic carbon (TOC) is achieved when both plants and bacteria were employed. The study, therefore, suggests that P. australis in combination with efficient bacteria can be a suitable choice to FTWs for phenol-degradation in water.     

Investigation of deleterious effects of nsSNPs in the POT1 gene: a structural genomics-based approach to understand the mechanism of cancer development

Protection of telomere 1 (POT1) is one of the key components of shelterin complex, implicated in maintaining the telomere homeostasis, and thus stability of the eukaryotic genome. A large number of non-synonymous single nucleotide polymorphisms (nsSNPs) in the POT1 gene have been reported to cause varieties of human diseases, including cancer. In recent years, a number of mutations in POT1 has been markedly increased, and interpreting the effect of these large numbers of mutations to understand the mechanism of associated diseases seems impossible using experimental approaches. Herein, we employ varieties of computational methods such as PROVEAN, PolyPhen-2, SIFT, PoPMuSiC, SDM2, STRUM, and MAESTRO to identify the effects of 387 nsSNPs on the structure and function of POT1 protein. We have identified about 183 nsSNPs as deleterious and termed them as “high-confidence nsSNPs.” Distribution of these high-confidence nsSNPs demonstrates that the mutation in oligonucleotide binding domain 1 is highly deleterious (one in every three nsSNPs), and high-confidence nsSNPs show a strong correlation with residue conservation. The structure analysis provides a detailed insights into the structural changes occurred in consequence of conserved mutations which lead to the cancer progression. This study, for the first time, offers a newer prospective on the role of POT1 mutations on the structure, function, and their relation to associated diseases.