Field evaluation of biosurfactants, surfactin and di-rhamnolipid produced by subsp. (VCRC B471) and (VCRC B426) against immature stages of the urban malaria vector .

Background & Objectives: Bacillus subtilis subsp. subtilis (VCRC B471) and Pseudomonas fluorescens (B426) produce mosquitocidal biosurfactant, surfactin and di-rhamnolipid. The objective of the study was to carry out a small-scale field evaluation of the two biosurfactants to determine the efficacy, application dosage, residual activity and frequency of application against Anopheles stephensi immatures in selected sites in Goa, India.

WDP formulations using a novel mosquitocidal bacteria, Bacillus thuringiensis subsp. israelensis/tochigiensis (VCRC B-474) - Development and storage stability.

A novel mosquito active strain, Bacillus thuringiensis (VCRC B474) sharing the antigens of 2 serotypes, namely israelensis &tochigiensis was characterized by scanning electron microscopy and SDS-PAGE. The spherical and ovoid crystals present in this strain was composed of major polypeptides the size of 28, 65, and 130 kDa respectively. The sporulated cell mass was formulated into water dispersible powder (WDP) formulations with different carrier materials and checked for activity against Culex quinquefasciatus larvae at monthly intervals for up to a year.

Molecular characterization of bmyC gene of the mosquito pupicidal bacteria, Bacillus amyloliquefaciens (VCRC B483) and in silico analysis of bacillomycin D synthetase C protein.

A strain of Bacillus amyloliquefaciens (VCRC B483) exhibiting mosquito pupicidal, keratinase and antimicrobial activities was isolated from mangrove forest ecosystem of Andaman and Nicobar Islands. Molecular characterization of the strain showed the presence of lipopeptide encoding bmyC gene. Phylogenetic tree based on protein sequence of this gene exhibited homology with mycosubtilin synthetase of Bacilus atropheus and Iturin synthetase of Bacillus subtilis and B.

Fly ash-based water dispersible powder formulation of var. : Development & laboratory evaluation against mosquito immatures.

Background & Objectives: Bacillus thuringiensis var. israelensis (Bti) formulations are presently being used for insect control. In this study, a water dispersible powder (WDP) formulation using fly ash (FA) as a carrier material was developed and studied for its activity against the larval stages of major mosquito vector species.

Bionomics of Anopheles fluviatilis and Anopheles culicifacies (Diptera: Culicidae) in Relation to Malaria Transmission in East-Central India.

The southern districts of Odisha State in east-central India have been highly endemic for falciparum malaria for many decades. However, there is no adequate information on the abundance of the vector species or their bionomics in relation to space and time in these districts. Therefore, a study was carried out on the entomological aspects of malaria transmission to generate such information.

Fly ash based Bacillus thuringiensis var. israelensis formulation for use against Culex quinquefasciatus, the vector of filariasis in natural ecosystems.

Background & Objectives: Fly ash is produced in huge quantities by the various thermal power stations in India. This thermal waste has been employed as a carrier material in the preparation of a biopesticidal water dispersible powder (WDP) formulation for use against mosquitoes. In the present investigation, this newly developed fly ash based WDP formulation was evaluated in natural breeding habitats of mosquito.

Cost-effective medium for the production of mosquito pupicidal lipopeptide from Bacillus subtilis subsp. subtilis (VCRC B471).

Background & Objectives: A cyclic lipopeptide (CLP), surfactin produced by a strain of Bacillus subtilis subsp. subtilis (VCRC B471) was found to exhibit mosquitocidal activity. The present study was carried out to enhance the surfactin level using low cost material in the production medium.

Mosquitocidal Bacillus amyloliquefaciens: dynamics of growth & production of novel pupicidal biosurfactant.

Background & Objectives: A strain of Bacillus amyloliquefaciens (VCRC B483) producing mosquito larvicidal and pupicidal biosurfactant was isolated from mangrove forest soil. The present study was aimed at studying the kinetics of growth and production of the mosquitocidal biosurfactant by this bacterium.

Methods: Dynamics of growth, sporulation and production of mosquitocidal biosurfactant were studied by standard microbiological methods.

Evaluation of the mtDNA-COII Region Based Species Specific Assay for Identifying Members of the Anopheles culicifacies Species Complex.

Background: Anopheles culicifacies, a major malarial vector has been recognized as a complex of five sibling species, A, B, C, D and E. These sibling species exhibit varied vectorial capacity, host specificity and susceptibility to malarial parasites/ insecticides. In this study, a PCR assay developed earlier for distinguishing the five individual species was validated on samples of An.

Mosquito adulticidal activity of a biosurfactant produced by Bacillus subtilis subsp. subtilis.

Background: A biosurfactant, surfactin, produced by a strain of Bacillus subtilis subsp. subtilis (VCRC B471), was effective in killing mosquito larval and pupal stages. As it was lethal to the non-feeding pupal stage, it was presumed that it could kill the adult mosquitoes also.

Enhanced production of mosquitocidal cyclic lipopeptide from Bacillus subtilis subsp. subtilis.

Background & Objectives: A cyclic lipopeptide, surfactin produced by a strain of Bacillus subtilis subsp. subtilis (VCRC B471) was found to exhibit activity against both the larval and pupal stages of mosquitoes. The present study was aimed at increasing the production of the mosquitocidal metabolite by modifying the conventional medium.

Bacillus amyloliquefaciens: a mosquitocidal bacterium from mangrove forests of Andaman & Nicobar islands, India.

Samples collected from the mangrove forests of Andaman & Nicobar islands yielded a mosquitocidal bacterium, whose extracellular metabolite(s) exhibited mosquito larvicidal and pupicidal activity. The bacterium was isolated using standard microbiological methods and identified using classical biochemical tests and rpoB gene sequences. The mosquitocidal bacterium was identified as Bacillus amyloliquefaciens.

Species-diagnostic polymerase chain reaction assays for Phlebotomus argentipes and Phlebotomus papatasi, vectors of Leishmania.

Species-specific differences encountered in the nucleotide sequences of a highly variable region of the 18S rRNA gene were used to design a multiplex polymerase chain reaction (PCR) assay for the identification of Phlebotomus papatasi Scopoli and Phlebotomus argentipes An-nandale & Brunetti, vectors of Leishmania. This multiplex PCR assay uses a common forward primer and two reverse primers, which are specific for the two species. Amplification of a PCR product of size 788 bp indicates the presence of P.

Surfactin: a novel mosquitocidal biosurfactant produced by Bacillus subtilis ssp. subtilis (VCRC B471) and influence of abiotic factors on its pupicidal efficacy.

Aim: The rpoB gene of the mosquito pupicidal isolate Bacillus subtilis (VCRC B471) was amplified to confirm the subspecies as subtilis. The mosquito pupicidal activity expressed by the biosurfactant surfactin is novel, and hence, the influence of abiotic factors like pH, temperature of water and sunlight on its efficacy was studied under laboratory conditions.

Methods And Results: The rpoB gene amplicon of the bacterium (c.

Identification and characterization of a mosquito pupicidal metabolite of a Bacillus subtilis subsp. subtilis strain.

The culture supernatant of a strain of Bacillus subtilis subsp. subtilis isolated from mangrove forests of Andaman and Nicobar islands, India was found to kill larval and pupal stages of mosquitoes. A chloroform extract of the culture supernatant of the bacterium showed pupicidal effects at an LC(50) dose of 1 microg/ml.

Utility of the rDNA-ITS2-PCR assay in detecting the life stages of species S of Anopheles fluviatilis complex.

Background & Objective: Anopheles fluviatilis, which ranks second among the major malarial vectors in India occurs as a complex of three morphologically identical species (species S, T and U) of which only species S is a vector. Hence, it becomes pertinent to have a method for the detection of this vector species under field conditions to map the distribution of this vector. An rDNA-ITS2-PCR assay has been developed earlier for species S of this complex using female adult specimens.

Nanoscale organization of hedgehog is essential for long-range signaling.

Hedgehog (Hh) plays crucial roles in tissue-patterning and activates signaling in Patched (Ptc)-expressing cells. Paracrine signaling requires release and transport over many cell diameters away by a process that requires interaction with heparan sulfate proteoglycans (HSPGs). Here, we examine the organization of functional, fluorescently tagged variants in living cells by using optical imaging, FRET microscopy, and mutational studies guided by bioinformatics prediction.

Retention of mosquito larvicidal activity of lyophilized cells and WDP formulation of Bacillus thuringiensis var. israelensis on long-term storage.

Lyophilized cells (sealed and unsealed) and water dispersible powders (WDPs) of two indigenous isolates of Bacillus thuringiensis var.israelensis were stored at -10, 4, 30 and 40 degrees C for up to 4 years and checked for activity. Lyophilized cells stored in sealed condition at -10, 4 and 30 degrees C and WDPs stored at -10 and 4 degrees C were found to maintain the activity fairly well.

Coconut water as a cheap source for the production of delta endotoxin of Bacillus thuringiensis var. israelensis, a mosquito control agent.

Bacillus thuringiensis var. israelensis (B. t.

rDNA-ITS2-PCR assay for grouping the cryptic species of Anopheles culicifacies complex (Diptera: Culicidae).

Anopheles culicifacies, a predominant vector of malaria in India exists as a complex of five sibling species A, B, C, D and E, of which, except species B, all the rest are vectors with varying vectorial capacities. With a combination of PCR assays, it is possible to identify all the five members of this species complex. These assays include amplification of the rDNA-ITS2 region followed by digestion of the ITS2 amplicon using restriction enzyme, Rsa I which groups the five members of the An.

Enhanced structure prediction of gene products containing class III adenylyl cyclase domains.

Domain finding algorithms are useful to understand overall domain architecture and to propose biological function to gene products. Automated methods of applying these tools to large-scale genome studies often employ stringent thresholds to recognize sequence domains. The realization of additional domains can be tedious involving manual intervention but can lead to better understanding of overall biological function.

Reappearance of Anopheles minimus in Singhbum hills of East-Central India.

Anopheles minimus, an important malaria vector of South East Asia, has reappeared in the Singhbum hills, East-Central India where deforestation and DDT residual spraying had reportedly eliminated it during the Malaria Eradication Programme. The species reported has been identified as sibling species A of the An. minimus complex.

Native and modeled disulfide bonds in proteins: knowledge-based approaches toward structure prediction of disulfide-rich polypeptides.

Structure prediction and three-dimensional modeling of disulfide-rich systems are challenging due to the limited number of such folds in the structural databank. We exploit the stereochemical compatibility of substructures in known protein structures to accommodate disulfide bonds in predicting the structures of disulfide-rich polypeptides directly from disulfide connectivity pattern and amino acid sequence in the absence of structural homologs and any other structural information. This knowledge-based approach is illustrated using structure prediction of 40 nonredundant bioactive disulfide-rich polypeptides such as toxins, growth factors, and endothelins available in the structural databank.