02224nas a2200205   4500008004100000245011400041210006900155260000800224300001200232490000700244520150600251100001701757700001801774700002101792700002201813700001601835700001701851700002501868856012501893       2016                        eng d00aMolecular cloning and in silico studies of physiologically significant trehalase from drosophila melanogaster0 aMolecular cloning and in silico studies of physiologically signi  cNOV  a282-2920 v923 aTrehalase, a physiologically important glycosidase is known for its crucial role in insect glycometabolism and stress recovery. The present study describes the molecular cloning of a gene fragment, encoding the catalytically active trehalase from Drosophila melanogaster (DmTre) and its heterologous expression in Escherichia coli. The 1275 bp gene was overexpressed in two different vectors viz., pET28a and pCOLD TF and investigated for variable soluble expression, purification and activity of the recombinant enzyme with optimum pH and temperature of enzyme as 6 and 55 degrees C, respectively. The sequence was characterized in silico by subjecting it to homology search, multiple sequence alignment and phylogenetic tree construction revealing its identity to other trehalases which belong to glycoside hydrolase family 37. The deduced amino acid sequence and modeled 3D structure of DmTre possessed all features of trehalase superfamily, including signature motifs and catalytic domain. The active site pocket of recombinant DmTre was compared with the crystal structure of E. coli trehalase identifying Glu424 and Asp226 as the putative catalytic residues. Additionally, enzyme-substrate docking suggests possible involvement of other residues in the catalysis along with Asp226. The present study holds significance in understanding the structural aspects of Drosophila trehalase in spite of unavailabilty of eukaryotic trehalase crystal structure. (C) 2016 Elsevier B.V. All rights reserved.1 aShukla, Ekta1 aThorat, Leena1 aBhavnani, Varsha1 aBendre, Ameya, D.1 aPal, J., K.1 aNath, B., B.1 aGaikwad, Sushama, M.  uhttps://library.ncl.res.in/content/molecular-cloning-and-silico-studies-physiologically-significant-trehalase-drosophila01888nas a2200181   4500008004100000245014700041210006900188260000800257300002500265490000600290520116900296100001801465700002201483700002201505700002501527700002401552856013001576       2017                        eng d00aHigh-throughput mass spectrometry analysis revealed a role for glucosamine in potentiating recovery following desiccation stress in chironomus0 aHighthroughput mass spectrometry analysis revealed a role for gl  cJUN  aArticle Number: 36590 v73 aDesiccation tolerance is an essential survival trait, especially in tropical aquatic organisms that are vulnerable to severe challenges posed by hydroperiodicity patterns in their habitats, characterized by dehydration-rehydration cycles. Here, we report a novel role for glucosamine as a desiccation stress-responsive metabolite in the underexplored tropical aquatic midge, Chironomus ramosus. Using high-throughput liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QToF-MS) analysis, biochemical assays and gene expression studies, we confirmed that glucosamine was essential during the recovery phase in C. ramosus larvae. Additionally, we demonstrated that trehalose, a known stress-protectant was crucial during desiccation but did not offer any advantage to the larvae during recovery. Based on our findings, we emphasise on the collaborative interplay of glucosamine and trehalose in conferring overall resilience to desiccation stress and propose the involvement of the trehalose-chitin metabolic interface in insects as one of the stress-management strategies to potentiate recovery post desiccation through recruitment of glucosamine.1 aThorat, Leena1 aOulkar, Dasharath1 aBanerjee, Kaushik1 aGaikwad, Sushama, M.1 aNath, Bimalendu, B.  uhttps://library.ncl.res.in/content/high-throughput-mass-spectrometry-analysis-revealed-role-glucosamine-potentiating-recovery02644nas a2200277   4500008004100000022001400041245011100055210006900166260000800235300000800243490000600251520174300257653002102000653002302021653001102044653002402055653001402079100001702093700001802110700002202128700002002150700002102170700002402191700002502215856012602240       2018                        eng d  a2190-572X00aCloning and characterization of trehalase: a conserved glycosidase from oriental midge, Chironomus ramosus0 aCloning and characterization of trehalase a conserved glycosidas  cAUG  a3520 v83 a<p>Insect trehalase is a multiferous enzyme, crucial for normal physiological functions as well as under stress conditions. In this report, we present a fundamental study of the trehalase gene segment (1587 bp) from Chironomus ramosus (CrTre) encoding for 529 amino acids, using appropriate bioinformatics tools. C. ramosus, a tropical midge is an emerging animal model to investigate the consequences of environmental stresses. We observed that CrTre belongs to GH family 37 in the CAZy database and possess 57-92% identity to dipteran trehalases. In silico characterization provided information regarding the structural, functional and evolutionary aspects of midge trehalase. In the phylogenetic tree, CrTre clustered with the soluble dipteran trehalases. Moreover, domain functional characterization of the deduced protein sequence by InterProScan (IPR001661), ProSite (PS00927 and PS00928) and Pfam (PF01204) indicated presence of highly conserved signature motifs which are important for the identification of trehalase superfamily. Furthermore, the instability index of CrTre was predicted to be &lt; 40 suggesting its in vivo stability while, the high aliphatic index indicated towards its thermal stability (index value 71-81). The modelled 3D tertiary structure of CrTre depicts a (alpha/alpha)(6) barrel toroidal core. The catalytic domain of the enzyme comprised Glu424 and Asp226 as the putative active site residues. Interestingly, the conserved motifs were observed to be formed by the flexible loopy regions in the tertiary structure. This study revealed essential sequence features of the midge trehalase and offers better insights into the structural aspects of this enzyme which can be correlated with its function.</p>10aConserved motifs10aHomology modelling10aMidges10aSecondary structure10atrehalose1 aShukla, Ekta1 aThorat, Leena1 aBendre, Ameya, D.1 aJadhav, Santosh1 aPal, Jayanta, K.1 aNath, Bimalendu, B.1 aGaikwad, Sushama, M.  uhttps://library.ncl.res.in/content/cloning-and-characterization-trehalase-conserved-glycosidase-oriental-midge-chironomus02434nas a2200277   4500008004100000022001400041245011600055210006900171260000900240300001200249490000800261520151600269653001501785653001501800653002801815653002701843653001501870653002001885100001801905700002101923700001701944700001701961700002201978700002402000856013202024       2020                        eng d  a0141-813000aStructural and physical analysis of underwater silk from housing nest composites of a tropical chironomid midge0 aStructural and physical analysis of underwater silk from housing  cNOV   a934-9420 v1633 a<p>Chironomids are an abundant group of aquatic silk spinning insects. They offer a unique opportunity of silk harvestation without killing them; however, they remained underappreciated models in silk research. Here, we investigate the structural and biomechanical characteristics of silk from the midge, Chironomus ramosus. A combination of microscopic (SEM), spectroscopic (CD and IR), structural (XRD), thermal (DSC and TGA) and mechanical measurement tools and techniques were employed to gain critical insights on midge silk. Maximum yield of silk was obtained from Chironomus in similar to 2.5 h, the shortest time reported among insects. The network of water-insoluble silk fibres possessed the smallest diameter of 110 +/- 35 nm, known for any insect silk, qualifying its superiority in fibre fineness. We demonstrate a cruelty-free silk extraction method in contrast to the conventional violent techniques. Structural characterization indicated coexistence of various secondary conformations, beta sheets being predominant. We compare and contrast these features to well-characterized caddisfly and silk-worm silks and highlight the uniqueness in midge silk that render mechanical stability and potentially contribute to its multi-functionalization. We thus propose Chironomus as an emerging candidate of water-borne silk, especially in the context of the `Peace silk' industry, aiming to develop non-violent methods for silk harvestation from animals. (C) 2020 Elsevier B.V. All rights reserved.</p>
10abiopolymer10aChironomus10aCommercial applications10aHousing nest composite10aPeace silk10aUnderwater silk1 aThorat, Leena1 aJoseph, Emmanuel1 aNisal, Anuya1 aShukla, Ekta1 aRaviKumar, Ameeta1 aNath, Bimalendu, B.  uhttps://library.ncl.res.in/content/structural-and-physical-analysis-underwater-silk-housing-nest-composites-tropical-chironomid