Albirhodobacter marinus gen. nov., sp. nov., a member of the family Rhodobacteraceae isolated from sea shore water of Visakhapatnam, India

A novel marine, Gram-negative, rod-shaped bacterium, designated strain N9^T, was isolated from a water sample of the sea shore at Visakhapatnam, Andhra Pradesh (India). Strain N9^T was found to be positive for oxidase and catalase activities. The fatty acids were found to be dominated by C_16:0, C_18:1 ω7c and summed in feature 3 (C_16:1 ω7c and/or C_16:1 ω6c). Strain N9^T was determined to contain Q-10 as the major respiratory quinone and phosphatidylethanolamine, phosphatidylglycerol, two aminophospholipids, two phospholipids and four unidentified lipids as polar lipids. The DNA G+C content of the strain N9^T was found to be 63 mol%. 16S rRNA gene sequence analysis indicated that Rhodobacter sphaeroides, Rhodobacter johrii, Pseudorhodobacter ferrugineus, Rhodobacter azotoformans, Rhodobacter ovatus and Pseudorhodobacter aquimaris were the nearest phylogenetic neighbours, with pair-wise sequence similarities of 95.43, 95.36, 94.24, 95.31, 95.60 and 94.74 %, respectively. Phylogenetic analysis showed that strain N9^T formed a distinct branch within the family Rhodobacteraceae and clustered with the clade comprising species of the genus Pseudorhodobacter, together with species of the genera Roseicitreum, Roseinatronobacter, Roseibaca and Rhodobaca. Species of the genus Pseudorhodobacter are phylogenetically close with a 16S rRNA gene sequence dissimilarity of 5.9–7.3 % (92.7–94.1 % similarity). Based on the above-mentioned phenotypic characteristics and on phylogenetic inference, strain N9^T is proposed as a representative of a new genus and a novel species of the family Rhodobacteraceae as Albirhodobacter marinus gen. nov., sp. nov. The type strain of Albirhodobacter marinus is N9 (= MTCC 11277^T = JCM 17680^T).     

Long-chain alkanes: allelochemicals for host location by the insect pest, Epilachna dodecastigma (Coleoptera: Coccinellidae)

Extraction, thin-layer chromatography, and gas chromatography–mass spectrometry of leaf surface waxes of Momordica charantia L. (Cucurbitaceae) revealed that 20 n-alkanes between n-C₁₅ and n-C₃₆, except n-C₃₄ and n-C₃₅, commonly occur in young, mature, and senescent stages. Hentriacontane, hentriacontane, and hexatriacontane were the predominant compounds in young, mature, and senescent leaves, respectively. The cuticular alkanes from young, mature, and senescent leaves attracted the female insect, Epilachna dodecastigma (Wied.), at 25–400, 25–400, and 100–400 μg concentrations, respectively, whereas the mixtures of synthetic alkanes mimicking cuticular alkanes of young, mature, and senescent leaves showed attraction at 100–400, 100–400, and 200–400 μg concentrations, respectively, in Y-shaped glass tube olfactometer bioassay. The difference in insect attraction is probably due to the absence of branched-chain alkanes in the synthetic mixtures. Individual synthetic heptacosane, nonacosane, and hentriacontane at 28.19–56.90, 32.04–64.08, and 60.44–120.88 μg, respectively, elicited attraction of the insect. A synthetic blend of 4.82, 4.91, 5.71, 6.74, 56.39, 7.94, 62.42, 120.88, and 36.33 μg of nonadecane, eicosane, heneicosane, pentacosane, heptacosane, octacosane, nonacosane, hentriacontane, and tritriacontane, respectively, was most attractive to the insect.     

An automated annotation tool for genomic DNA sequences using GeneScan and BLAST

Genomic sequence data are often available well before the annotated sequence is published. We present a method for analysis of genomic DNA to identify coding sequences using the GeneScan algorithm and characterize these resultant sequences by BLAST. The routines are used to develop a system for automated annotation of genome DNA sequences.     

Development of Acid-Resistant Alginate/Trimethyl Chitosan Nanoparticles Containing Cationic β-Cyclodextrin Polymers for Insulin Oral Delivery

In this study, the use of trimethylchitosan (TMC), by higher solubility in comparison with chitosan, in alginate/chitosan nanoparticles containing cationic β-cyclodextrin polymers (CPβCDs) has been studied, with the aim of increasing insulin uptake by nanoparticles. Firstly, TMCs were synthesized by iodomethane, and CPβCDs were synthesized within a one-step polycondensation reaction using choline chloride (CC) and epichlorohydrine (EP). Insulin–CβCDPs complex was prepared by mixing 1:1 portion of insulin and CPβCDs solutions. Then, nanoparticles prepared in a three-step procedure based on the iono-tropic pregelation method. Nanoparticles screened using experimental design and Placket Burman methodology to obtain minimum size and polydispercity index (pdI) and the highest entrapment efficiency (EE). CPβCDs and TMC solution concentration and pH and alginate and calcium chloride solution concentrations are found as the significant parameters on size, PdI, and EE. The nanoparticles with proper physicochemical properties were obtained; the size, PdI, and EE% of optimized nanoparticles were reported as 150.82 ± 21 nm, 0.362 ± 0.036, and 93.2% ± 4.1, respectively. The cumulative insulin release in intestinal condition achieved was 50.2% during 6 h. By SEM imaging, separate, spherical, and nonaggregated nanoparticles were found. In the cytotoxicity studies on Caco-2 cell culture, no significant cytotoxicity was observed in 5 h of incubation, but after 24 h of incubation, viability was decreased to 50% in 0.5 mμ of TMC concentration. Permeability studies across Caco-2 cells had been carried out, and permeability achieved in 240 min was 8.41 ± 0.39%, which shows noticeable increase in comparison with chitosan nanoparticles. Thus, according to the results, the optimized nanoparticles can be used as a new insulin oral delivery system.KEY WORDS: alginate, cationic β-cyclodextrin, insulin nanoparticle, oral delivery, trimethyl chitosan     

The nucleolar channel system of human endometrium is related to endoplasmic reticulum and R-rings

The nucleolar channel system (NCS) is a well-established ultrastructural hallmark of the postovulation endometrium. Its transient presence has been associated with human fertility. Nevertheless, the biogenesis, composition, and function of these intranuclear membrane cisternae are unknown. Membrane systems with a striking ultrastructural resemblance to the NCS, termed R-rings, are induced in nuclei of tissue culture cells by overexpression of the central repeat domain of the nucleolar protein Nopp140. Here we provide a first molecular characterization of the NCS and compare the biogenesis of these two enigmatic organelles. Like the R-rings, the NCS consists of endoplasmic reticulum harboring the marker glucose-6-phosphatase. R-ring formation initiates at the nuclear envelope, apparently by a calcium-mediated Nopp140-membrane interaction, as supported by the calcium-binding ability of Nopp140, the inhibition of R-ring formation by calcium chelators, and the concentration of Nopp140 and complexed calcium in R-rings. Although biogenesis of the NCS may initiate similarly, the reduced presence of complexed calcium and Nopp140 suggests the involvement of additional factors.     

Loss of CCR7 Expression on CD56bright NK Cells Is Associated with a CD56dimCD16+ NK Cell-Like Phenotype and Correlates with HIV Viral Load

NK cells are pivotal sentinels of the innate immune system and distinct subpopulations in peripheral blood have been described. A number of studies addressed HIV-induced alterations of NK cell phenotype and functionality mainly focusing on CD56^dimCD16⁺ and CD56⁻CD16⁺ NK cells. However, the impact of HIV-infection on CD56^bright NK cells is less well understood. Here we report a rise of CD56^bright NK cells in HIV-infected individuals, which lack CCR7-expression and strongly correlate with HIV viral load. CCR7⁻CD56^bright NK cells were characterized by increased cytolytic potential, higher activation states and a more differentiated phenotype. These cells thus acquired a number of features of CD56^dimCD16⁺ NK cells. Furthermore, CD56^bright NK cells from HIV patients exhibited higher degranulation levels compared to uninfected individuals. Thus, chronic HIV-infection is associated with a phenotypic and functional shift of CD56^bright NK cells, which provides a novel aspect of HIV-associated pathogenesis within the NK cell compartment.