Molecular basis

Objectives of the thesis: Identifying genetic diversity and basic genetic parameters as a basis for creating a high-quality genetic variation of tiger shrimp for initial breeding of tiger shrimp according to growth traits.

25p tunelove 11-06-2021 16 3   Download

Completely and systematic study of taxonomy of the Cashew family (Anacardiaceae) in Vietnam, based on evidence of morphology and molecular biology, as a scientific basis for the compilation of Flora of Vietnam about Anacardiaceae in Vietnam.

27p angicungduoc11 17-04-2021 20 4   Download

Understanding the genetic complexity of traits is an important objective of small grain temperate cereals yield and adaptation improvements. Bi-parental quantitative trait loci (QTL) linkage mapping is a powerful method to identify genetic regions that co-segregate in the trait of interest within the research population. However, recently, association or linkage disequilibrium (LD) mapping using a genome-wide association study (GWAS) became an approach for unraveling the molecular genetic basis underlying the natural phenotypic variation.

17p partimesinhvien 08-05-2020 17 1   Download

The transcription factor serum response factor (SRF) regulates expression of growth factor-dependent genes and muscle-specific genes in vertebrates. Homologous factors regulate differentiation of some ectodermic tissues in invertebrates. To explore the molecular basis of these different physiological functions, the functionality of human, Drosophila melanogaster and Artemia franciscana SRFs in mammalian cells has been compared in this article. D. melanogaster and, to a lesser extend, A.

9p system191 01-06-2013 34 5   Download

The design of b-glycosidases with planed substrate specificity for biotechnological application has received little attention. This is mostly a consequence of the lack of data on the molecular basis of the b-glycosidase specificity, namely data on the energy of the noncovalent interactions in the enzymetransition state complex. In an attempt to fill this gap, sitedirected mutagenesis and enzyme steady-state kinetic experiments with different substrates were conducted, using as model a digestive b-glycosidase (glycoside hydrolase family 1) from Spodoptera frugiperda (Lepidoptera) (Sfbgly50).

10p system191 01-06-2013 44 4   Download

A recombinant lipase cloned from Pseudomonas fragi strain IFO 3458 (PFL) was found to retain significant activity at low temperature. In an attempt to elucidate the structural basis of this behaviour, a model of its three-dimensional structure was built by homology and compared with homologous mesophilic lipases, i.e. the Pseudomonas aeruginosa lipase (45% sequence identity) and Burkholderia cepacia lipase (38%).

8p system191 01-06-2013 49 4   Download

Introducing site-directed mutations in surface-exposed residues of subunit II of the heme aa3 cytochrome c oxidase of Paracoccus denitrificans, we analyze the kinetic parameters of electron transfer from reduced horse heart cytochrome c. Specifically we address the following issues: (a) which residues on oxidase contribute to the docking site for cytochrome c, (b) is an aromatic side chain required for electron entry from cytochrome c, and (c) what is the molecular basis for the previously observed biphasic reaction kinetics....

9p system191 01-06-2013 37 3   Download

The apparent molecular mass of human milk bile salt-stimulated lipase (BSSL) varies between mothers. The molecular basis for this is unknown, but indirect evidence has suggested the di€erences to reside in a region of repeats located in the C-terminal part of the protein. We here report that a polymorphism within exon 11 of the BSSLgene is the explanation for the molecular variants of BSSL found in milk.

9p research12 01-06-2013 45 4   Download

Two-dimensional NMR and molecular dynamics simula-tions have been used to determine the three-dimensional structures of two hairpin DNA structures: d-CTAGAG GATCCUTTTGGATCCT (abbreviated as U1-hairpin) and d-CTAGAGGATCCTTUTGGATCCT (abbreviated as U3-hairpin). The 1 H resonances of both of these hairpin structures have been assigned almost completely.

9p research12 23-04-2013 21 3   Download

We examined the microenvironment of the single trypto-phan and the tyrosine residues of PsbQ, one of the three main extrinsic proteins of green algal and higher plant photosystem II. On the basis of this information and the previous data on secondary structure [Balsera, M., Arel-lano, J.B., Gutie´rrez, J.R., Heredia, P., Revuelta, J.L. & De Las Rivas, J. (2003)Biochemistry42, 1000–1007], we screened structural models derived by combining various threading approaches.

12p tumor12 20-04-2013 33 1   Download

The catalytic activity of phenylalanine hydroxylase (PAH, phenylalanine 4-monooxygenase EC 1.14.16.1) is regulated by three main mechanisms, i.e. substrate (L-phenylalanine, L-Phe) activation, pterin cofactor inhibition and phos-phorylation of a single serine (Ser16) residue.To address the molecular basis for the inhibition by the natural cofactor (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin, its effects on the recombinant tetrameric human enzyme (wt-hPAH) was studied using three different conformational probes, i.e.

10p tumor12 20-04-2013 36 3   Download

HIV-1 protease (PR) and two drug-resistant variants – PR with the V82A mutation (PRV82A) and PR with the I84V mutation (PRI84V) – were studied using reduced peptide analogs of five natural cleavage sites (CA-p2, p2-NC, p6 pol -PR, p1-p6 and NC-p1) to understand the structural and kine-tic changes. The common drug-resistant mutations V82A and I84V alter residues forming the substrate-binding site. Eight crystal structures were refined at resolutions of 1.10–1.60 A ˚ .

13p fptmusic 12-04-2013 38 2   Download

Embryos and larvae of the brine shrimp,Artemia francis-cana, were shown previously to possess a protein, now termed p49, which cross-links microtubules in vitro. Molecular characteristics of p49 were described, but the protein’s identity and its role in the cell were not determined. Degenerate oligonucleotide primers designed on the basis of peptide sequence obtained by Edman degradation during this studywereusedtogeneratep49cDNAsbyRT-PCRand thesewere clonedand sequenced.

11p fptmusic 12-04-2013 51 2   Download

The low affinity of peptide nucleic acid (PNA) to hybridize with DNA in the presence of a mismatch endows PNA with a high degree of discriminat-ory capacity that has been exploited in therapeutics for the selective inhibi-tion of the expression of point-mutated genes. To obtain a structural basis for this intriguing property, molecular dynamics simulations are carried out on PNAÆDNA duplexes formed at the Ki-ras proto-oncogene, compri-sing the point-mutated (GAT), and the corresponding wild-type (GGT) codon 12. ...

16p fptmusic 11-04-2013 53 2   Download

Glutamine is an essential amino acid for enterocytes, especially in states of critical illness and injury. In several studies it has been speculated that the beneficial effects of glutamine are dependent on the route of supply (lumi-nal or systemic). The aim of this study was to investigate the relevance of both routes of glutamine delivery toin vitro intestinal cells and to explore the molecular basis for proposed beneficial glutamine effects: (a) by deter-mining the relative uptake of radiolabelled glutamine in Caco-2 cells;...

15p fptmusic 11-04-2013 47 2   Download

The crystal structures of the wild-type HIV-1 protease (PR) and the two resistant variants, PRV82Aand PRL90M,have been determined in complex with the antiviral drug, indi-navir, to gain insight into the molecular basis of drug resistance. V82A and L90M correspond to an active site mutation and nonactive site mutation, respectively. The inhibition (Ki)of PRV82Aand PRL90Mwas 3.3- and 0.16-fold, respectively, relative to the value for PR. They showed only a modest decrease, of 10–15%, in theirkcat /Kmvalues relative to PR. ...

9p dell39 03-04-2013 28 3   Download

Bacillus cereusisolated from the larvae of Myrmeleon bore was found to secrete proteins that paralyze and kill German cockroaches, Blattela germanica, when injected. One of these active proteins was purified from the culture broth ofB.cereususing anion-exchange and gel-filtration chro-matography. The purified toxin, with a molecular mass of 34 kDa, was identified as sphingomyelinase C (EC3.1.4.12) on the basis of its N-terminal and internal amino-acid sequences. A recombinant sphingomyelinase C expressed in Escherichia coliwas as potent as the native protein in killing the cockroaches....

6p dell39 03-04-2013 51 4   Download

The molecular basis of the transferrin (TF)–transferrin receptor (TFR) interaction is not known. The C-lobe of TF is required to facilitate binding to the TFR and both the N- and C-lobes are necessary for maximal bind-ing. Several mAb have been raised against human transferrin (hTF). One of these, designated F11, is specific to the C-lobe of hTF and does not recognize mouse or pig TF.

10p dell39 27-03-2013 36 3   Download

The formation of amyloid fibrils is associated with various human medical disorders of unrelated origin. Recent research indicates that self-assembled amyloid fibrils are also involved in physiological processes in several micro-organisms. Yet, the molecular basis for the recognition and self-assembly processes mediating the formation of such structures from their soluble protein precursors is not fully understood.

8p dell39 27-03-2013 38 5   Download

Thepcd1mutant of pea lacks heme oxygenase (HO) activity required for the synthesis of the phytochrome chromophore and is consequently severely deficient in all responses mediated by the phytochrome family of plant photoreceptors. Here we describe the isolation of the gene encoding pea heme oxygenase 1 (PsHO1) and confirm the presence of a mutation in this gene in the pcd1 mutant.

13p inspiron33 26-03-2013 56 4   Download