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1.  Can We Disrupt the Sensing of Honey Bees by the Bee Parasite Varroa destructor? 
PLoS ONE  2014;9(9):e106889.
The ectoparasitic mite, Varroa destructor, is considered to be one of the most significant threats to apiculture around the world. Chemical cues are known to play a significant role in the host-finding behavior of Varroa. The mites distinguish between bees from different task groups, and prefer nurses over foragers. We examined the possibility of disrupting the Varroa – honey bee interaction by targeting the mite's olfactory system. In particular, we examined the effect of volatile compounds, ethers of cis 5-(2′-hydroxyethyl) cyclopent-2-en-1-ol or of dihydroquinone, resorcinol or catechol. We tested the effect of these compounds on the Varroa chemosensory organ by electrophysiology and on behavior in a choice bioassay. The electrophysiological studies were conducted on the isolated foreleg. In the behavioral bioassay, the mite's preference between a nurse and a forager bee was evaluated.
Principal findings
We found that in the presence of some compounds, the response of the Varroa chemosensory organ to honey bee headspace volatiles significantly decreased. This effect was dose dependent and, for some of the compounds, long lasting (>1 min). Furthermore, disruption of the Varroa volatile detection was accompanied by a reversal of the mite's preference from a nurse to a forager bee. Long-term inhibition of the electrophysiological responses of mites to the tested compounds was a good predictor for an alteration in the mite's host preference.
These data indicate the potential of the selected compounds to disrupt the Varroa - honey bee associations, thus opening new avenues for Varroa control.
PMCID: PMC4167332  PMID: 25226388
2.  Agromyces arachidis sp. nov. Isolated from a Peanut (Arachis hypogaea) Crop Field 
A Gram-positive, yellowish bacterium strain AK-1T was isolated from soil sample collected from peanut (Arachis hypogaea) crop field and studied by using a polyphasic approach. The organism had morphological and chemotaxonomic properties consistent with its classification in the genus Agromyces. Phylogenetic analysis of the 16S rRNA gene sequence showed that strain AK-1T was closely related to Agromyces aurantiacus (98.6%) followed by Agromyces soli (98.3%), Agromyces tropicus (97.6%), Agromyces ulmi (97.3%), Agromyces flavus (97.2%), and Agromyces italicus (97.0%), whereas the sequence similarity values with respect to the other Agromyces species with validly published names were between 95.3 and 96.7 %. However, the DNA-DNA hybridization values obtained between strain AK-1T and other related strains were well below the threshold that is required for the proposal of a novel species. The DNA G + C content of the strain is 71.8 mol%. The above data in combination with the phenotypic distinctiveness of AK-1T clearly indicate that the strain represents a novel species, for which the name Agromyces arachidis sp. nov. is proposed. The type strain is AK-1T (=MTCC 10524T = JCM 19251T).
PMCID: PMC3855984  PMID: 24348566
3.  Vitellogenin from the Silkworm, Bombyx mori: An Effective Anti-Bacterial Agent 
PLoS ONE  2013;8(9):e73005.
Silkworm, Bombyx mori, vitellogenin (Vg) was isolated from perivisceral fat body of day 3 of pupa. Both Vg subunits were co-purified as verified by mass spectrometry and immunoblot. Purified Vg responded to specific tests for major posttranslational modifications on native gels indicating its nature as lipo-glyco-phosphoprotein. The Vg fraction had strong antibacterial activity against Gram negative bacterium Escherichia coli and Gram positive bacterium Bacillus subtilis. Microscopic images showed binding of Vg to bacterial cells and their destruction. When infected silkworm larvae were treated with purified Vg they survived the full life cycle in contrast to untreated animals. This result showed that Vg has the ability to inhibit the proliferation of bacteria in the silkworm fluid system without disturbing the regular metabolism of the host.
PMCID: PMC3772815  PMID: 24058454
4.  Draft Genome Sequence of Streptomyces gancidicus Strain BKS 13-15 
Genome Announcements  2013;1(2):e00150-13.
We report the 7.3-Mbp genome sequence of Streptomyces gancidicus strain BKS 13-15, isolated from mangrove sediment samples collected from the Bhitar Kanika Mangrove Reserve Forest, Odissha, India. The draft genome of strain Streptomyces gancidicus strain BKS 13-15 consists of 7,300,479 bp with 72.6% G+C content, 6,631 protein-coding genes, and 71 RNAs.
PMCID: PMC3630403  PMID: 23599292
5.  Draft Genome Sequence of Acinetobacter baumannii Strain MSP4-16 
Genome Announcements  2013;1(2):e00137-13.
We report the 4.0-Mb draft genome sequence of Acinetobacter baumannii strain MSP4-16, isolated from a mangrove soil sample from Parangipettai (11°30′N, 79°47′E), Tamil Nadu, India. The draft genome sequence of strain MSP4-16 consists of 3,944,542 bp, with a G+C content of 39%, 5,387 protein coding genes, and 69 RNAs.
PMCID: PMC3622989  PMID: 23558533
6.  siMacro: A Fast and Easy Data Processing Tool for Cell-Based Genomewide siRNA Screens 
Genomics & Informatics  2013;11(1):55-57.
Growing numbers of studies employ cell line-based systematic short interfering RNA (siRNA) screens to study gene functions and to identify drug targets. As multiple sources of variations that are unique to siRNA screens exist, there is a growing demand for a computational tool that generates normalized values and standardized scores. However, only a few tools have been available so far with limited usability. Here, we present siMacro, a fast and easy-to-use Microsoft Office Excel-based tool with a graphic user interface, designed to process single-condition or two-condition synthetic screen datasets. siMacro normalizes position and batch effects, censors outlier samples, and calculates Z-scores and robust Z-scores, with a spreadsheet output of >120,000 samples in under 1 minute.
PMCID: PMC3630387  PMID: 23613684
high-throughput screening assays; RNA interference
7.  A proteomic view on the developmental transfer of homologous 30 kDa lipoproteins from peripheral fat body to perivisceral fat body via hemolymph in silkworm, Bombyx mori 
BMC Biochemistry  2012;13:5.
A group of abundant proteins of ~30 kDa is synthesized in silkworm larval peripheral fat body (PPFB) tissues and transported into the open circulatory system (hemolymph) in a time-depended fashion to be eventually stored as granules in the pupal perivisceral fat body (PVFB) tissues for adult development during the non-feeding stage. These proteins have been shown to act anti-apoptotic besides being assigned roles in embryogenesis and defense. However, detailed protein structural information for individual PPFB and PVFB tissues during larval and pupal developmental stages is still missing. Gel electrophoresis and chromatography were used to separate the 30 kDa proteins from both PPFB and PVFB as well as hemolymph total proteomes. Mass spectrometry (MS) was employed to elucidate individual protein sequences. Furthermore, 30 kDa proteins were purified and biochemically characterized.
One- and two-dimensional gel electrophoresis (1/2D-PAGE) was used to visualize the relative changes of abundance of the 30 kDa proteins in PPFB and PVFB as well as hemolymph from day 1 of V instar larval stage to day 6 of pupal stage. Their concentrations were markedly increased in hemolymph and PVFB up to the first two days of pupal development and these proteins were consumed during development of the adult insect. Typically, three protein bands were observed (~29, 30, 31 kDa) in 1D-PAGE, which were subjected to MS-based protein identification along with spots excised from 2D-gels run for those proteomes. Gas phase fragmentation was used to generate peptide sequence information, which was matched to the available nucleotide data pool of more than ten highly homologous insect 30 kDa lipoproteins. Phylogenetic and similarity analyses of those sequences were performed to assist in the assignment of experimentally identified peptides to known sequences. Lipoproteins LP1 to LP5 and L301/302 could be matched to peptides extracted from all bands suggesting the presence of full length and truncated or modified protein forms in all of them. The individual variants could not be easily separated by classical means of purification such as 2D-PAGE because of their high similarity. They even seemed to aggregate as was indicated by native gel electrophoresis. Multistep chromatographic procedures eventually allowed purification of an LP3-like protein. The protein responded to lipoprotein-specific staining.
In B. mori larvae and pupae, 30 kDa lipoproteins LP1 to LP5 and L301/302 were detected in PPFB and PVFB tissue as well as in hemolymph. The concentration of these proteins changed progressively during development from their synthesis in PPFB, transport in hemolymph to storage in PVFB. While the 30 kDa proteins could be reproducibly separated in three bands electrophoretically, the exact nature of the individual protein forms present in those bands remained partially ambiguous. The amino acid sequences of all known 30 kDa proteins showed very high homology. High-resolution separation techniques will be necessary before MS and other structural analysis can shed more light on the complexity of the 30 kDa subproteome in B. mori. A first attempt to that end allowed isolation of a B. mori LP3-like protein, the complete structure, properties and function of which will now be elucidated in detail.
PMCID: PMC3306753  PMID: 22369700
8.  INDUS - a composition-based approach for rapid and accurate taxonomic classification of metagenomic sequences 
BMC Genomics  2011;12(Suppl 3):S4.
Taxonomic classification of metagenomic sequences is the first step in metagenomic analysis. Existing taxonomic classification approaches are of two types, similarity-based and composition-based. Similarity-based approaches, though accurate and specific, are extremely slow. Since, metagenomic projects generate millions of sequences, adopting similarity-based approaches becomes virtually infeasible for research groups having modest computational resources. In this study, we present INDUS - a composition-based approach that incorporates the following novel features. First, INDUS discards the 'one genome-one composition' model adopted by existing compositional approaches. Second, INDUS uses 'compositional distance' information for identifying appropriate assignment levels. Third, INDUS incorporates steps that attempt to reduce biases due to database representation.
INDUS is able to rapidly classify sequences in both simulated and real metagenomic sequence data sets with classification efficiency significantly higher than existing composition-based approaches. Although the classification efficiency of INDUS is observed to be comparable to those by similarity-based approaches, the binning time (as compared to alignment based approaches) is 23-33 times lower.
Given it's rapid execution time, and high levels of classification efficiency, INDUS is expected to be of immense interest to researchers working in metagenomics and microbial ecology.
A web-server for the INDUS algorithm is available at
PMCID: PMC3333187  PMID: 22369237

Results 1-8 (8)