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Los Humeros volcanic complex, located at the eastern end of the Trans Mexican Volcanic Belt, possess superficial thermal manifestations (fumaroles, heat steam-soils and alteration zones), with temperatures between 50 °C and 90 °C. This is the first work to explore the bacterial diversity of a steam soil of Los Humeros geothermal field using a metagenomic 16S RNA gene analysis, and the presence of lipolytic enzymes' genes after an enrichment culture by a whole-genome shotgun approach. High diversity indexes were found in soil samples, with Firmicutes, Chloroflexi, Proteobacteria, Actinobacteria and Acidobacteria as the most prevalent phyla. Alicyclobacillus was the most prevalent genus at 15 cm and Anoxybacillus at 50 cm depth; anaerobic and obligate thermophilic and hyperthermophilic members were found at 50 cm depth. Firmicutes was favored by the oil-rich medium, and the dominant genera were Geobacillus and Caldibacillus. 165 genes related to lipolytic enzymes were found; carboxilesterases and phospholipases C were the most abundant, and 43% were assigned to uncharacterized lipolytic enzymes. The diversity as well as the high percentage of non-characterized lipolytic enzymes found after soil enrichment in an oil-rich medium suggest the presence of biotechnologically promising organisms and enzymes that deserve to be investigated. [ABSTRACT FROM AUTHOR]

Differences in sensitivity to 6- n-propylthiouracil (PROP) are associated with TAS2R38 genotypes. Those differences allow the classification in 'nontasters' (NT), 'tasters' (MT) and 'supertasters' (ST), which have been related to differences in taste acuity and nutritional status, although there is controversy in the results obtained by different research groups. The aim of this study was to determine the frequencies of NT, MT and ST, TAS2R38 genotypes and to analyze its relationship with taste sensitivity, food consumption and anthropometric measures in healthy Mexican adults. Body Mass Index (BMI), Waist Circumference (WC), TAS2R38 genotype, detection thresholds for sucrose, capsaicin, PROP and linoleic acid as well as intensity perceived for sucrose, capsaicin and PROP suprathreshold solutions were performed in 76 Mexican adults. Food restriction was assessed and two seven-day food consumption records from 66 individuals were analyzed. The proportion of subjects with genotype AVI/AVI, and its associated phenotype NT, was close to 10%; the proportion of MT and ST was 54.6 and 31.8 respectively. Genotypes associated with ST were present in 38%, while those associated with MT accounted for 41% of the population. PROP sensitivity was associated with linoleic acid sensitivity, consumption of vegetables, grains and dairy foods. BMI and WC were negatively correlated to carbohydrate intake and linoleic acid detection threshold. PROP taster status and TAS2R38 genotypes were related. PROP and linoleic acid sensitivity influences food consumption in unrestrained eaters and could produce differences in long-term nutritional status. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]