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Beneficial symbionts are horizontally or vertically transmitted to offspring, relying on host- or microbe-mediated mechanisms for colonisation. While multiple studies on symbionts transmitted internally or by feeding highlight host adaptations and dynamics of symbiont colonisation, less is known for beneficial microbes colonising host external surfaces, such as the insect cuticle. Here, we investigate the colonisation dynamics of a bacterial symbiont that protects eggs and larvae of Lagria villosa beetles against pathogens. After maternal application to the egg surface, symbionts colonise specialized cuticular invaginations on the dorsal surface of larvae. We assessed the colonisation time point and investigated the involvement of the host during this process. Symbionts remain on the egg surface before hatching, providing protection. Immediately after hatching, cells from the egg surface colonise the larvae and horizontal acquisition can occur, yet efficiency decreases with increasing larval age. Additionally, passive or host-aided translocation likely supports colonization of the larval symbiotic organs. This may be especially important for the dominant non-motile symbiont strain, while motility of additional strains in the symbiont community might also play a role. Our findings provide insights into colonisation dynamics of cuticle-associated defensive symbionts and suggest alternate or complementary strategies used by different strains for colonization.

The present study was an attempt to understand the sexual dimor-phism of the integumentary scent glands of soft-furred field rat Millardia meltada from the perspectives of anatomy, morphology and histology with view to correlate with the sex-specific pheromones they produce. The scent gland of male is known as preputial gland, and female, the clitoral gland. The rats, that are agricultural pests were field caught, the glands of males and females of almost identical size were dissected out, and subjected to gravimetric, morphometric and histological analyses. Both glands are yellowish-brown, pear-shaped, and dorsoventrally compressed. The mean weight, length and width of preputial glands are significantly (p < 0.05) larger than that of the clitoral glands. The preputial gland is composed of sebaceous glandular lobules and apocrine glandular lobules whereas the clitoral gland is formed only of sebaceous glandular lobules. The sebaceous glandular lobules of both preputial and clitoral glands are filled with a wax-like material. Thus, the scent glands of the soft-furred male field rats exhibit sexual dimorphism in respect histoarchitecture of the glands and the nature of the secretory material. This sexual dimorphism of the scent glands may reflect control by male and female sex hormones impinging on specific roles as sex attractant pheromones.

A synergistic catalyst was architectured using the hydrothermal crystallization method. Mesoporous material with pore diameter less than 20 nm was grown on the microporous Zeolite HY. The catalysts were characterized by XRD, ICP-OES, BET, TPD, SEM and TEM techniques. The SEM picture portrayed excellent core - shell morphology and TEM analysis corresponded to the XRD reports. Mahua oil was cracked in a pilot scale reactor over the synthesized catalysts at an optimized reaction condition (Temperature: 400

Inferring the function of genes by manipulating their activity is an essential tool for understanding the genetic underpinnings of most biological processes. Advances in molecular microbiology have seen the emergence of diverse mutagenesis techniques for the manipulation of genes. Among them, transposon-insertion sequencing (Tn-seq) is a valuable tool to simultaneously assess the functionality of many candidate genes in an untargeted way. The technique has been key to identify molecular mechanisms for the colonization of eukaryotic hosts in several pathogenic microbes and a few beneficial symbionts. Here, Tn-seq is established as a method to identify colonization factors in a mutualistic Burkholderia gladioli symbiont of the beetle Lagria villosa. By conjugation, Tn5 transposon-mediated insertion of an antibiotic-resistance cassette is carried out at random genomic locations in B. gladioli. To identify the effect of gene disruptions on the ability of the bacteria to colonize the beetle host, the generated B. gladioli transposon-mutant library is inoculated on the beetle eggs, while a control is grown in vitro in a liquid culture medium. After allowing sufficient time for colonization, DNA is extracted from the in vivo and in vitro grown libraries. Following a DNA library preparation protocol, the DNA samples are prepared for transposon-insertion sequencing. DNA fragments that contain the transposon-insert edge and flanking bacterial DNA are selected, and the mutation sites are determined by sequencing away from the transposon-insert edge. Finally, by analyzing and comparing the frequencies of each mutant between the in vivo and in vitro libraries, the importance of specific symbiont genes during beetle colonization can be predicted.

Environmental concerns have initiated the search for greener measures to mitigate pollution issues. Bio Nano CaO was synthesized by reducing CaO extracted from chicken egg shell using tea decoction. The synthesized material was characterized by physico-chemical techniques such as XRD, TGA, BET surface area analyser, TGA and SEM techniques. XRD studied confirmed the crystalline nature of material. The prepared material was found to be stable till 450

In order to get high degradation efficiency in the visible region, different concentrations of active transition metals such as nickel and ruthenium were impregnated over titania synthesised by sol–gel method. The physico chemical properties of the catalysts were studied by various instrumental techniques such as X-ray diffraction, UV–visible diffuse reflectance spectroscopy, BET surface area analysis, Transmission Electron Microscopy, FT-IR spectroscopy, Raman Spectroscopy and X-ray photoelectron spectroscopy. The photocatalytic decolourisation/degradation of a widely used dye namely Amidoblack-10B was studied over metal loaded titania under both UV and visible light irradiations and monitored by using UV–visible spectrophotometer/TOC analyser. Photocatalytic activities of bare and metal titania catalysts were compared. The optimised reaction parameters for the complete decolourisation of AB-10B over bare titania under UV irradiation were found to be: 0.15 g of TiO 2 , 3 × 10 −4 M [AB-10B] at its natural pH. Among the catalysts, Ni/TiO 2 (1%) and Ru/TiO 2 (1%) decolourised completely 100% at 330 min and 210 min with rate constant values of 9.39 × 10 −3 min −1 and 2.3 × 10 −2 min −1 respectively. Both nickel and ruthenium were found to be recyclable upto 3 cycles without any loss in their photocatalytic activities. The extent of degradation of Amidoblack-10B and its mineralisation were confirmed further by HPLC.