Determination of iduronic acid and glucuronic acid in sulfated chondroitin/dermatan hybrid chains by <Superscript>1</Superscript>H-nuclear magnetic resonance spectroscopy

The relative proportion of L-iduronic acid (IdoA) and D-glucuronic acid (GlcA) is of great importance for the structure–function relationship of chondroitin sulfate (CS)/dermatan sulfate (DS). However, determination of the isotypes of uronic acid residues in CS/DS is still a challenge, due to the instability of free uronic acid released by chemical degradation and its conversion to unsaturated uronic acid by digestion with bacterial eliminase. ¹H-Nuclear magnetic resonance (NMR) spectroscopy is a promising tool with which to address this issue, but the traditional method based on the assignment of the ring proton signals of IdoA and GlcA residues still has drawbacks such as the serious overlap of signals in the ¹H-NMR spectrum of CS/DS polysaccharides. We found that the proton signals of the N-acetyl group of N-acetyl-D-galactosamines in CS and DS could be clearly distinguished and accurately integrated in the one-dimensional (1D) ¹H-NMR spectrum. Based on this finding, here we report a novel, sensitive, and nondestructive 1D ¹H-NMR-based method to determine the proportion of IdoA and GlcA residues in CS/DS hybrid chains. The contributions of Fuchuan Li and Shuhei Yamada should be considered equal.     

Effects of sex chromosome aneuploidy on male sexual behavior

Incidence of sex chromosome aneuploidy in men is as high as 1:500. The predominant conditions are an additional Y chromosome (47,XYY) or an additional X chromosome (47,XXY). Behavioral studies using animal models of these conditions are rare. To assess the role of sex chromosome aneuploidy on sexual behavior, we used mice with a spontaneous mutation on the Y chromosome in which the testis-determining gene Sry is deleted (referred to as Y⁻) and insertion of a Sry transgene on an autosome. Dams were aneuploid (XXY⁻) and the sires had an inserted Sry transgene (XY Sry ). Litters contained six male genotypes, XY, XYY⁻, XX Sry , XXY⁻ Sry , XY Sry and XYY⁻ Sry . In order to eliminate possible differences in levels of testosterone, all of the subjects were castrated and received testosterone implants prior to tests for male sex behavior. Mice with an additional copy of the Y⁻ chromosome (XYY⁻) had shorter latencies to intromit and achieve ejaculations than XY males. In a comparison of the four genotypes bearing the Sry transgene, males with two copies of the X chromosome (XX Sry and XXY⁻ Sry ) had longer latencies to mount and thrust than males with only one copy of the X chromosome (XY Sry and XYY⁻ Sry ) and decreased frequencies of mounts and intromissions as compared with XY Sry males. The results implicate novel roles for sex chromosome genes in sexual behaviors.     

Antimicrobial activity against select food-borne pathogens by phenolic antioxidants enriched in cranberry pomace by solid-state bioprocessing using the food grade fungus Rhizopus oligosporus

Listeria monocytogenes, Vibrio parahaemolyticus and Escherichia coli 0157:H7 are important food-borne pathogens. Control of these pathogens using synthetic antimicrobials such as currently approved antibiotics is challenging due to potential development of resistance. A profile of antimicrobials compared to a single compound could be potentially more effective. Cranberry pomace is a byproduct of the cranberry processing industry. Solid-state bioprocessing of cranberry pomace using the food grade fungus Rhizopus oligosporus improves phenolic and antioxidant profiles. We hypothesize that these phytochemicals mobilized during pomace bioprocessing could improve the antimicrobial functionality. The objective of this research was to use the food grade fungus R. oligosporus to release phenolic aglycones and relate its antioxidant functionality and diphenyl mobilization to antimicrobial activity against L. monocytogenes, V. parahaemolyticus and E. coli 0157:H7. Bioprocessing of pomace was done for 20 days with R. oligosporus. Total phenolics in water extracts were assayed using a Folin-Ciocalteu method. The antioxidant potential was measured using a β-carotene oxidation system (APF) and 1,1-diphenyl-2-picrylhydrazyl-radical (DPPH) system. Changes in phenolic profiles were analyzed using HPLC. Antimicrobial activities of the extracts during growth were tested using standard disk assays. Soluble phenolics, antioxidant activity and ellagic acid concentrations were enriched by bioprocessing and antimicrobial activity of the extracts against L. monocytogenes and V. parahaemolyticus correlated with highest soluble phenolics and APF in the same extracts. For E. coli 0157:H7 inhibition correlated with the extracts corresponding to highest DPPH and ellagic acid concentration. The bioprocessing-based antimicrobial activity depended on different phenolic functional properties of the extracts. Sensitivity towards soluble phenolics reflected in DPPH activity suggested inhibition by the disruption of the membrane by hyperacidification. Whereas, sensitivity to APF and ellagic acid suggests potential antimicrobial activity by membrane-transport disruption. The variation in sensitivity of pathogens has implications for designing new food grade antimicrobials. This bioprocessing strategy can be an innovative approach to produce broad spectrum antimicrobials against important food-borne pathogens.     

Inheritance of downy mildew resistance, β-1,3-glucanases and peroxidases in pearl millet [Pennisetum glaucum (L.) R. Br.] crosses

The inheritance of resistance to downy mildew disease and the defense-related enzymes β-1,3-glucanase and peroxidase was studied in crosses of pearl millet using a generation-mean analysis. The study material comprised six generations (susceptible and resistant parents, F₁, F₂, BC₁ and BC₂) in three crosses. Seedlings from these generations were inoculated with the downy mildew pathogen Sclerospora graminicola and disease incidence was recorded. Analysis of constitutive levels of β-1,3-glucanase and peroxidase in the seedlings of different generations indicated that the resistant populations showed higher enzyme activities, while lower activities of the enzymes were recorded in the susceptible populations. In the generation-mean analysis, the significance of scaling tests revealed the existence of non-allelic interactions in the inheritance of resistance to downy mildew as well as with the enzymes. Among the gene effects, both additive and dominant effects were significant. All the non-allelic interaction effects were significant in the crosses. Studies on the isozyme patterns of the enzymes substantiated the results of the disease-incidence experiments in most of the generations. The results indicated that the inheritance of downy mildew disease resistance and the expression of β-1,3-glucanase and peroxidase in pearl millet is not only under the control of additive and dominant genes but are also governed by complex non-allelic interactions. Received: 30 April 2000 / Accepted: 17 October 2000     

A Mass Spectrometric Study for Comparative Analysis and Evaluation of Metabolite Recovery from Plasma by Various Solvent Systems

A solvent system that extracts a maximum number of metabolites belonging to diverse chemical classes from complex biofluids, such as plasma, may offer useful inputs to understand the metabolic and physiological state of an individual. The present study compared seven solvent systems for extraction of metabolites from plasma. The extracts were analyzed by mass spectrometry (MS) and MS/MS (MS2) using a quadrupole time-of-flight liquid chromatography/MS system in positive and negative modes of ionization. Metabolites with molecular mass below 400 were identified using Human Metabolome Database MS2 and MS search interfaces. The acetone/isopropanol (2:1) system yielded promising results in positive ionization mode, as the maximum number of MS and MS2 features was detected in the extract. It was found to be superior in extraction of various classes of metabolites, especially organic acids, nucleosides and nucleoside derivatives, and heterocyclic molecules. Glycerophosphocholines in the mass range of 400–700 were found to be efficiently extracted by the methanol/chloroform/water (8:1:1) system. In negative mode as well, the maximum number of MS2 features was detected in methanol/chloroform/water and acetone/isopropanol extracts. The fingerprints of molecular features obtained in the negative and positive modes differed from each other to a significant extent.     

Regulation of Selenocysteine Incorporation into the Selenium Transport Protein,Selenoprotein P

Selenoproteins are unique as they contain selenium in their active site in the form of the 21st amino acid selenocysteine (Sec), which is encoded by an in-frame UGA stop codon. Sec incorporation requires both cis- and trans-acting factors, which are known to be sufficient for Sec incorporation in vitro, albeit with low efficiency. However, the abundance of the naturally occurring selenoprotein that contains 10 Sec residues (SEPP1) suggests that processive and efficient Sec incorporation occurs in vivo. Here, we set out to study native SEPP1 synthesis in vitro to identify factors that regulate processivity and efficiency. Deletion analysis of the long and conserved 3′-UTR has revealed that the incorporation of multiple Sec residues is inherently processive requiring only the SECIS elements but surprisingly responsive to the selenium concentration. We provide evidence that processive Sec incorporation is linked to selenium utilization and that reconstitution of known Sec incorporation factors in a wheat germ lysate does not permit multiple Sec incorporation events, thus suggesting a role for yet unidentified mammalian-specific processes or factors. The relationship between our findings and the channeling theory of translational efficiency is discussed.     

Genome Sequence of Janibacter hoylei MTCC8307, Isolated from the Stratospheric Air

Janibacter hoylei MTCC8307 was isolated from stratospheric air at an altitude of 41.4 km over Hyderabad, India. Here, we present the draft genome of Janibacter hoylei MTCC8307, which contains 3,139,099 bp with a G+C content of 72.8 mol%, 2,972 protein-coding genes, and 57 structural RNAs.     

Pest management services through conservation of biological control agents: review,case studies and field experiences

ABSTRACT

Conservation biological control is an approach to enhance the efficacy of natural enemies by ensuring their availability in an agro-ecosystem on a long temporal scale. An increased survival often leads to better fecundity and improved behaviour of the natural enemies, which in turn ensures sustainable pest management. This paper, apart from being a concise review of conservation biological control, deals with selected India-specific case studies and field experiences on habitat manipulation and refugia. Results from a Bengaluru-based study during 2012–2015 on conservation biological control in an organic mango ecosystem are also presented. It also dwells briefly on conservation of insectivorous birds and touches upon conservation biocontrol with respect to entomopathogenic microorganisms and plant disease antagonists.