Lower Neighborhood Socioeconomic Status Associated with Reduced Diversity of the Colonic Microbiota in Healthy Adults

In the United States, there are persistent and widening socioeconomic gaps in morbidity and mortality from chronic diseases. Although most disparities research focuses on person-level socioeconomic-status, mounting evidence suggest that chronic diseases also pattern by the demographic characteristics of neighborhoods. Yet the biological mechanisms underlying these associations are poorly understood. There is increasing recognition that chronic diseases share common pathogenic features, some of which involve alterations in the composition, diversity, and functioning of the gut microbiota. This study examined whether socioeconomic-status was associated with alpha-diversity of the colonic microbiota. Forty-four healthy adults underwent un-prepped sigmoidoscopy, during which mucosal biopsies and fecal samples were collected. Subjects’ zip codes were geocoded, and census data was used to form a composite indicator of neighborhood socioeconomic-status, reflecting household income, educational attainment, employment status, and home value. In unadjusted analyses, neighborhood socioeconomic-status explained 12–18 percent of the variability in alpha-diversity of colonic microbiota. The direction of these associations was positive, meaning that as neighborhood socioeconomic-status increased, so did alpha-diversity of both the colonic sigmoid mucosa and fecal microbiota. The strength of these associations persisted when models were expanded to include covariates reflecting potential demographic (age, gender, race/ethnicity) and lifestyle (adiposity, alcohol use, smoking) confounds. In these models neighborhood socioeconomic-status continued to explain 11–22 percent of the variability in diversity indicators. Further analyses suggested these patterns reflected socioeconomic variations in evenness, but not richness, of microbial communities residing in the sigmoid. We also found indications that residence in neighborhoods of higher socioeconomic-status was associated with a greater abundance of Bacteroides and a lower abundance of Prevotella, suggesting that diet potentially underlies differences in microbiota composition. These findings suggest the presence of socioeconomic variations in colonic microbiota diversity. Future research should explore whether these variations contribute to disparities in chronic disease outcomes.     

Biochemical characterization of an alkaline surfactant-stable keratinase from a new keratinase producer,Bacillus zhangzhouensis

A new keratinase producer, Bacillus sp. BK111, isolated from a poultry feather was identified as Bacillus zhangzhouensis, which is the first report for its keratinolytic activity. The keratinase production was optimized, followed by the enzyme purification and characterization using biochemical assays. A 2.34-fold increase was observed in the enzyme production under optimized conditions. The enzyme was characterized as a serine protease with 42 kDa molecular weight, stable in a wide range of temperature and pH with maximum keratinolytic activity at 60 °C and pH 9.5. The enzyme had a wide range of different substrates with the best performance on the feather meal substrate. Metal ions of Ca²⁺, K⁺, Na⁺ and Mn²⁺ enhanced the enzyme activity. The enzyme showed a great deal of stability in the presence of ethanol, methanol, acetone, 2-propanol, dimethyl sulfoxide, Tween-80 and Triton X-100. Dithiothreitol (DTT), as a reducing agent, caused a twofold increase in keratinolytic activity. The half-life of the enzyme at optimum temperature was calculated to be 125 min and the ratio of keratinolytic:caseinolytic for the enzyme was 0.8. Our results showed the remarkable features of the enzyme that make it suitable for biotechnological usages.

     

Immune response variations to Salmonella enterica serovar Typhi recombinant porin proteins in mice

ObjectivesTyphoid fever is caused by Salmonella enterica serovar Typhi. OmpC, OmpF and OmpA, the three major outer membrane proteins (OMPs), could serve as vaccine candidates.MethodsThe porins antigenicity was predicted in silico. The OMP genes were amplified, cloned and expressed. Sero-reactivities of the recombinant proteins purified by denaturing method were assayed by ELISA. BALB/c mice were immunized with the recombinant porins followed by bacterial challenge.ResultsBacterial challenge of the animal model brought about antibody triggering efficacy of the antigen in OmpF > OmpC > OmpA order. Experimental findings validated the in silico results. None of the antigens had synergic or antagonistic effects on each other from immune system induction points of view. Despite their high immunogenicity, none of the antigens was protective. However, administration of two or three antigens simultaneously resulted in retardation of lethal effect. Porins, in addition to their specific functions, share common functions. Hence, they can compensate for each other's functions.ConclusionsThe produced antibodies could not eliminate the pathogenicity by blockade of one or some of the antigens. Porin antigens are not suitable vaccine candidates alone or in denatured forms. Native forms of the antigens maybe studied for protective immunogenicity.     

An introduction to Iranian Collembola (Hexapoda): an?update to the species list

The Collembola fauna of Iran is little known and no comprehensive examination of this group of Hexapoda is available for this region. The only notable work on Collembola was carried out by Cox (1982). Recently, studies on the Collembola fauna have started in several regions. In this paper, publications by different researchers are documented and the species that have been found in different regions of Iran until January 2013 are listed. At present, 112 species, belonging to 18 families and 57 genera are known from Iran.     

Assessment of genetic diversity of cultivated and wild Iranian grape germplasm using retrotransposon-microsatellite amplified polymorphism (REMAP) markers and pomological traits

Molecular Biology Reports - Understanding the genetic diversity and relationships between genotypes is an effective step in designing effective breeding programs. Insertional polymorphisms of...     

Differential Effects of Ornithine Enantiomers on the Activity of Anti‐oxidant Enzymes,Polyamines Content,and Growth of Tobacco Cells under Osmotic Stresses

Ornithine (Orn) plays an essential role in the metabolism of plant cells through incorporation in polyamines biosynthesis, the urea cycle and nitrogen metabolism. Herein, we show that Orn enantiomers have different effects on anti‐oxidant enzymes activities, polyamines and proline biosynthesis and also an alleviation effect of osmotic stresses on tobacco cells. The type of stress has a significant impact on the function of L‐ and D‐Orn for improvement of the stress effect on the cells. Under saline conditions, both enantiomers restored cell growth, though D‐Orn was more beneficial to some extent. This was accompanied with a higher biosynthesis of putrescine, proline, and up‐regulated activity of certain anti‐oxidant enzymes by D‐Orn. Under drought stress conditions, a distinct differential behavior emerged and only L‐Orn showed an alleviative effect on the cell growth. Regulation of hydrogen peroxide content via the activity of catalase/peroxidase and production of osmolytes, e.g., proline and fructans, was dependent on the type of enantiomers. Activity of anti‐oxidant enzymes and production of malondialdehyde from cell membranes were differently regulated following treatment with either Orn enantiomer. The results suggest that management of H₂O₂ content is a determining feature of the function of Orn enantiomers in tobacco cells under salinity and drought stress conditions. Chirality 25:583–588, 2013. © 2013 Wiley Periodicals, Inc.