Evidence of Wolbachia Symbiont in Aedes Mosquitoes from Karnataka, India

Wolbachia a group of obligate intracellular maternally inherited bacteria found in several arthropod groups. These endosymbionts behave as a reproductive parasite by manipulating host reproduction to enhance their vertical transmission. One of the reproductive modifications, cytoplasmic incompatibility, has received much attention for its role in applied strategies targeting economically important insect pests and disease vectors. The present molecular studies, provides evidence for Wolbachia symbiont in Aedes mosquito species such as Ae. aegypti, Ae. albopictus & Ae. vitatus which are potential vectors of Chikungunya & Dengue viruses were collected from different locations of Karnataka. The results reveal Wolbachia AB super group infections in Ae. albopictus mosquitoes. This study is facilitates to assess the prevalence of the endosymbionts in important mosquito vectors from different geographical locations of India. Consequently, the prevalence of these endosymbionts in Aedes albopictus provides the fundamental implication for devising control strategies

Molecular strain typing of Wolbachia infection from Indian mosquitoes using wsp gene

Objective: To determine the status of Wolbachia subgroup and phylogenetic relationships in Indian mosquitoes. Methods: Recently we reported Wolbachia infection in eight out of twenty field-caught mosquito species of India, using wsp specific primers. DNA extracted from these mosquito species were used for PCR amplification and sequencing. Results: Wolbachia A harboured in Aedes albopictus and Culex gelidus belongs to the subgroup AlbA whereas Wolbachia B harboured in Aedes albopictus and Culex quinquefasciatus belongs to the subgroup Pip and of Culex vishnui belongs to subgroup Con. However, Wolbachia harboured in Armigeres subalbatus, Armigeres kesseli, Culex sitiens and Toxorhynchites splendens could not be placed into any known subgroup and may represent other unknown strains of Wolbachia. Our phylogenetic analysis revealed eight novel Wolbachia strains, four in the A group and four in the B group. Most of the Wolbachia strains present in Indian mosquitoes belong to the Albo, Pip and Con groups. Conclusions: The similarities and differences between Wolbachia strains infecting different mosquito species are fundamental for estimating how easily mosquitoes acquire new infections. © 2011 Asian Pacific Tropical Medicine Press

Simple and efficient procedure for the one-pot synthesis of β-acetamido-β-aryl-propiophenones by molecular iodine-catalyzed tandem reaction

Molecular iodine efficiently catalyzes the four-component tandem reaction of araldehydes, arylmethyl ketones, acetyl chloride, and acetonitrile to afford the corresponding β-acetamido-β-aryl-propiophenones. The new protocol gives high yields of the products, and the reactions go to completion within 10-15 min on a hot plate at 80-85°C. Copyright © Taylor & Francis Group, LLC

A preliminary survey for Wolbachia and bacteriophage WO infections in Indian mosquitoes (Diptera: Culicidae)

Maternally inherited Wolbachia endosymbiotic bacteria are known to induce various kinds of reproductive alterations in their arthropod hosts. It has been proposed that this bacterium can be used as a tool for gene drive system in mosquitoes and also for the reduction of population size and modulating population age structure in order to reduce disease transmission. In the present study, we carried out a survey to determine the prevalence of Wolbachia and its phage WO infection in Indian mosquitoes and classified Wolbachia infection into groups A and B based on extensive polymerase chain reaction assay using Wolbachia specific wsp and orf7 gene primers. Out of 20 fieldcaught mosquito species, eight species have shown to be infected. Singly infected with Wolbachia A was found in two species and B group found in four species, while double infection with AB group were found in two species. All the screened mosquito species with positive Wolbachia infection were also infected with phage WO. The knowledge of variation in Wolbachia and phage WO infection rates and inferred susceptibility to infection among different mosquito genera has fundamental implications for designing and successful application of Wolbachia based vector-borne disease control strategies

A sensitive assay for ornithine amino transferase in rat brain mitochondria by ninhydrin method

To establish/develop an assay method for measuring Ornithine Aminotransferase (EC.2.6.1.13) activity using rat brain mitochondria as a source of enzyme in presence and absence of Pyridoxal Phosphate (PLP). The modified method, with the improved sensitivity, is adopted for the assay of ornithine amino transferase activity in rat brain mitochondria. The enzyme activity was measured at 620 nm, the study showed that reaction was optimum at 37°C for 30 minutes. The assay is sensitive enough to detect activity at the order of nanomoles pyrroline-5-carboxylate/mg protein/minute and can be compared as an alternative to the radio isotopic method which is more cumbersome and aminobenzaldehyde method which is less sensitive. The Km & V max shows maximum activity in the presence of Pyridoxal Phosphate (Coenzyme) concentration at 0.05mM when compared with absence of Pyridoxal Phosphate as higher the concentration of Pyridoxal Phosphate affects the affinity of the enzyme to substrate. The OAT activity in different tissues of the rat was also studied and highest activity was found in liver and kidney. © 2009 Association of Clinical Biochemists of India