Use of zinc chloride as alternative stimulant for in vitro study of nitric oxide production pathway in avian splenocyte culture.

Nitric Oxide (NO) plays an important role for regulation of cellular and vascular response of inflammation and initiates killing mechanism in the host-defense reactions. NO production is regulated through inducible nitric oxide synthase (iNOS) pathway in response to infections and injurious agents besides pro-inflammatory cytokines secreted by the host. Evaluation of NO pathway is one of the major targets which can evaluate various immunomodulators for their therapeutic interaction on innate immune system.

A report on the prevalence of gastrointestinal parasites in yaks (Bos poephagus) in the cold desert area of North Sikkim, India.

Faecal samples were collected from 348 yaks(Bos poephagus) in and around Gurudogmer Plateau, a cold desert area in North Sikkim, India. The prevalence of gastrointestinal parasitic infection was recorded at 10.05% in both the organized and traditionally managed farms of yak.

Polymorphism and natural selection of antigen B1 of Echinococcus granulosus isolated from different host assemblages in India.

Antigen B (AgB) is an excretory-secretory product of larval stage of Echinococcus granulosus. This antigen is abundantly secreted by larval stage of the worm. AgB is encoded by a multigene family and is suggested to be involved in evasion of host immune system.

Conserved water-mediated H-bonding dynamics of catalytic Asn 175 in plant thiol protease.

The role of invariant water molecules in the activity of plant cysteine protease is ubiquitous in nature. On analysing the 11 different Protein DataBank (PDB) structures of plant thiol proteases, the two invariant water molecules W1 and W2 (W220 and W222 in the template 1PPN structure) were observed to form H-bonds with the O b atom of Asn 175. Extensive energy minimization and molecular dynamics simulation studies up to 2 ns on all the PDB and solvated structures clearly revealed the involvement of the H-bonding association of the two water molecules in fixing the orientation of the asparagine residue of the catalytic triad.

An evaluation of antigen B family of Echinococcus granulosus, its conformational propensity and elucidation of the agretope.

The present communication evaluates the antigen B (AgB) family of bubaline isolates of Echinococcus granulosus with respect to their conformational propensity and also discusses the stretches of agretope. AgB, which is abundantly present in hydatid cyst fluid, is encoded by a gene family, AgB1-AgB5. Hydatidosis is of zoonotic and economic importance in India.

Molecular characterization of Echinococcus granulosus of Indian animal isolates on the basis of nuclear and mitochondrial genotype.

Sixty-six isolates of larval stage of Echinococcus granulosus, a known pathogenic parasite of man and animals were collected from cattle, buffalo, sheep, and goats. Single-stranded conformation polymorphism (SSCP) for analysis of variation after denaturation of amplicon of intron of actin II (ACTII) revealed six SSCP phenotypes. Intron portion was analyzed considering introns-early and introns-late theories.

Molecular appraisal of Indian animal isolates of Echinococcus granulosus.

Background & Objective: Cystic echinococcosis (CE) has a wide host range and distinct entities, not only reflected phenotypically but also by genotypic variation. Considering this fact, this study was undertaken to characterize the Indian isolates of Echinococcus granulosus to find out difference between Indian cattle, buffalo and sheep isolates on the basis of random amplification of polymorphic DNA (RAPD) PCR and PCR mediated restriction fragment length polymorphism (PCRRFLP) of internal transcribed spacer gene 1 (ITS1).

Methods: A total of 22 isolates of E.

Stressor-induced changes to the protoscoleces of Echinococcus granulosus of Indian buffalo origin.

In the present study viable protoscoleces of Echinococcus granulosus were exposed to in vitro anthelmintic treatment to observe efficacy against Indian buffalo isolates. Evaluation criteria included morphological changes, viability scores and expression of peptides as a product of prestressed protoscoleces. Protoscolex changes included presence of bladder-like structure and morphological distortion.

Thermodynamic characterization of a highly thermoactive extracellular pectate lyase from a new isolate Bacillus pumilus DKS1.

An extracellular pectate lyase (EC 4.2.2.

Crystal structure of the pyocyanin biosynthetic protein PhzS.

The human pathogen Pseudomonas aeruginosa produces pyocyanin, a blue-pigmented phenazine derivative, which is known to play a role in virulence. Pyocyanin is produced from chorismic acid via the phenazine pathway, nine proteins encoded by a gene cluster. Phenazine-1-carboxylic acid, the initial phenazine formed, is converted to pyocyanin in two steps that are catalyzed by the enzymes PhzM and PhzS.

Mutation scan screening of Echinococcus granulosus isolates of Indian origin.

During the present investigation a total of forty Indian animal isolates were screened by single strand conformation polymorphism (SSCP) collected from sheep, goat, cattle and buffalo. The result of the study indicated that nuclear variants of Echinococcus granulosus were present in both small and large ruminants. SSCP phenotypes of AgB, intron of actin II and Hbx-2 have been deduced.

Molecular modeling of the ternary complex of Rusticyanin-cytochrome c4-cytochrome oxidase: an insight to possible H-bond mediated recognition and electron transfer reaction in T. ferrooxidans.

The metabolism of Thiobacillus ferrooxidans involves electron transfer from the Fe+2 ions in the extracellular environment to the terminal oxygen in the bacterial cytoplasm through a series of periplasmic proteins like Rusticyanin (RCy), Cytochrome (Cyt c4), and Cytochrome oxidase (CcO). The energy minimization and MD studies reveal the stabilization of the three redox proteins in their ternary complex through the direct and water mediated H-bonds and electrostatic interaction. The surface exposed polar residues of the three proteins, i.

Modeling study of Rusticyanin-Cytochrome C(4) complex: an insight to possible H-bond mediated recognition and electron--transfer process.

Rusticyanin (RCy) mediated transfer of electron to Cytochrome C(4) (Cytc(4)) from the extracellular Fe(+2) ion is primarily involved in the Thiobacillus ferrooxidans induced bio-leaching of pyrite ore and also in the metabolism of this acidophilic bacteria. The modeling studies have revealed the two possible mode of RCy-Cytc(4) complexation involving nearly the same stabilization energy approximately -15 x 10(3) kJ/mol, one through N-terminal Asp 15 and another -C terminal Glu 121 of Cytc(4) with the Cu-bonded His 143 of RCy. The Asp 15:His 143 associated complex (DH) of Cytc(4)-RCy was stabilized by the intermolecular H-bonds of the carboxyl oxygen atoms O(delta1) and O(delta2) of Asp 15 with the Nepsilon-atom of His 143 and O(b) atoms of Ala 8 and Asp 5 (of Cytc(4)) with the Thr 146 and Phe 51 (of RCy).

Molecular basis of resistance to muramidase and cationic antimicrobial peptide activity of lysozyme in staphylococci.

It has been shown recently that modification of peptidoglycan by O-acetylation renders pathogenic staphylococci resistant to the muramidase activity of lysozyme. Here, we show that a Staphylococcus aureus double mutant defective in O-acetyltransferase A (OatA), and the glycopeptide resistance-associated two-component system, GraRS, is much more sensitive to lysozyme than S. aureus with the oatA mutation alone.

Cloning, sequencing and expression of cDNA of bovine neutrophil beta-defensin from water buffalo (Bubalus bubalis).

Neutrophil beta-defensins have been identified as naturally occurring potent antibacterial cationic peptides serving as effector molecules of innate immunity that provide a first line of defence against pathogens. Considering the broad-spectrum antimicrobial activity against microorganisms and role in innate immunity of the neutrophil beta-defensins, it has been characterized in many livestock species including cattle, sheep, caprine and porcines. Here we report the isolation, cloning, sequencing and expression of precursor bovine neutrophil beta-defensin isolated from Indian water buffalo.

Polymorphism discovery in 62 DNA repair genes and haplotype associations with risks for lung and head and neck cancers.

DNA repair is essential for the maintenance of genetic stability. We undertook sequencing to determine common genetic variants in 70 genes involved in three major repair pathways (base excision repair, nucleotide excision repair and mismatch repair) and in DNA synthesis, and investigated their relationship to lung and head and neck (H-N) cancers. Of the 70 genes examined, 62 were successfully screened (exon coverage >20%) by sequencing exons, parts of introns and flanking regions in 32 DNA samples from healthy Caucasian individuals.

Functional characterization of cis and trans activity of the Flavivirus NS2B-NS3 protease.

Flaviviruses are serious human pathogens for which treatments are generally lacking. The proteolytic maturation of the 375-kDa viral polyprotein is one target for antiviral development. The flavivirus serine protease consists of the N-terminal domain of the multifunctional nonstructural protein 3 (NS3) and an essential 40-residue cofactor (NS2B(40)) within viral protein NS2B.

Bending and unwinding of nucleic acid by prion protein.

Nucleic acid induces conformational changes in the prion protein (23-231 amino acids) to a structure resembling its pathological isoform. The prion protein, in turn, facilitates DNA strand transfer and acts as a DNA chaperone which is modulated by the N-terminal unstructured basic segment of the protein. Here we have studied the prion protein induced conformational changes in DNA using oligonucleotides covalently labeled with the energy donor fluorescein and the acceptor rhodamine moieties by fluorescence resonance energy transfer (FRET) and by thermal stability of the unlabeled oligonucleotides.

Biological polyamines inhibit nucleic-acid-induced polymerisation of prion protein.

Nucleic-acid-induced polymerisation of prion protein, when monitored by anilino naphthalene sulfonic acid dye, shows, successively, an immediate fluorescence increase of the dye upon mixing of the reactants, followed by a lag period in which the dye fluorescence remains unchanged, and then a phase in which dye fluorescence increases with time. The biological polyamines spermine and spermidine reduce the extent of the initial fluorescence increase, increase the lag period, and reduce both the rate and the extent of increase in fluorescence intensity of the dye in the final phase of the reaction. Spermidine is less effective than spermine in all of these processes.

Conserved water molecular dynamics of the different X-ray structures of rusticyanin: an unique aquation potentiality of the ligand bonded Cu++ center.

The invariant water molecular interaction involving in the Rusticyanin of Thiobacillus ferrooxidans is thought to be important for its molecular complexation with other proteins at differential acidophilic situation. The comparative analysis of the different x-ray, energy minimized, and auto solvated structures of Rusticyanin revealed the presence of five specific invariant bound water molecules (among the approximately 150 water molecules per monomer) in the crystals. The five W 205, W 206, W 112, W 214, and W 221 water molecules (in Rusticyanin PDB code: 1RCY) were seem to be invariant in all the seven structures (PDB codes: 1RCY, 1A3Z, 1A8Z, 1E3O, 1GY1, 1GY2, 2CAL).

Influence of wall teichoic acid on lysozyme resistance in Staphylococcus aureus.

Staphylococcus aureus peptidoglycan (PG) is completely resistant to the hydrolytic activity of lysozyme. Here we show that modifications in PG by O acetylation, wall teichoic acid, and a high degree of cross-linking contribute to this resistance.