Bacteroidales are attractive as water quality indicators because of their potential to discern sources of fecal pollution, and it is presumed that these bacteria do not multiply outside their host organisms. The persistence of a fecal Bacteroidales marker was monitored over 14 days in river water microcosms that varied in temperature from 10°C to 30°C and salinity from 0‰ to 30‰ by quantitative PCR (qPCR). Decay rates were estimated and compared to the results of other studies examining the survival and persistence of Bacteroidales markers by converting decay rates from other studies to a common decay rate unit. The log-linear decay rates estimated in this work ranged from ؊0.18 to ؊1.31 ln(C T /C 0 ) day ؊1 , where C T is the threshold cycle and C 0 is the concentration of cells at time zero, which is comparable to findings in previous studies. Salinity had a positive effect on Bacteroidales marker persistence, while decay was more rapid at higher temperatures. Comparison of 16S rRNA gene clone libraries generated from microcosm samples indicated that most of the operational taxonomic unit (OTU) and phylogenetic diversity was found within samples and not between samples, indicating at least qualitatively that diverse lineages persist and likely have similar survival characteristics under most of the conditions examined. It was noted that the samples at higher salinities also had the smallest amount of diversity between samples as well as the lowest decay rates. This research also highlights the need for a repository of raw survival and persistence data if more sophisticated models of decay are to be employed and compared between different studies.Fecal pollution has negative impacts from both environmental and economic perspectives. The presence of traditional fecal indicator bacteria (FIB), namely, Escherichia coli and Enterococcus, is the standard by which the extent of fecal contamination and potential health hazard is currently assessed for recreational waters. Determining the presence of FIB is a relatively easy task, but determining the source(s) is a considerably more complex problem. Molecular methods based on the identification of 16S rRNA gene markers of fecal Bacteroidales have been successfully applied to delineate the sources of fecal pollution based on differences in host species intestinal community compositions (9,20,34). Determination of the mere presence of different sources of fecal pollution by using host-specific Bacteroidales markers was a significant advance for water quality analysis. The next problem that presented itself was quantifying the relative contributions of fecal pollution from respective sources. Since the first Bacteroidales hostspecific molecular marker detection systems were published, studies have followed describing quantitative PCR (qPCR) methods for quantifying the abundance of specific markers (15,21,25,28) in natural samples. Although enumeration of the specific markers is currently possible, it is clear that host-specific marker quantities in natural waters do not d...

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Advances have been made to standardize 16S rRNA gene amplicon based studies for inter-study comparisons, yet there are many opportunities for systematic error that may render these comparisons improper and misleading. The fecal microbiome of horses has been examined previously, however, no universal horse fecal collection method and sample processing procedure has been established. This study was initialized in large part to ensure that samples collected by different individuals from different geographical areas (i.e., crowdsourced) were not contaminated due to less than optimal sampling or holding conditions. In this study, we examined the effect of sampling the surface of fecal pellets compared to homogenized fecal pellets, and also the effect of time of sampling after defecation on ‘bloom’ taxa (bloom taxa refers to microbial taxa that can grow rapidly in horse feces post-defecation) using v4 16S rRNA amplicon libraries. A total of 1,440,171 sequences were recovered from 65 horse fecal samples yielding a total of 3,422 OTUs at 97% similarity. Sampling from either surface or homogenized feces had no effect on diversity and little effect on microbial composition. Sampling at various time points (0, 2, 4, 6, 12 h) had a significant effect on both diversity and community composition of fecal samples. Alpha diversity (Shannon index) initially increased with time as regrowth taxa were detected in the amplicon libraries, but by 12 h the diversity sharply decreased as the community composition became dominated by a few bloom families, including Bacillaceae, Planococcaeae, and Enterococcaceae, and other families to a lesser extent. The results show that immediate sampling of horse feces must be done in order to ensure accurate representation of horse fecal samples. Also, several of the bloom taxa found in this study are known to occur in human and cattle feces post defecation. The dominance of these taxa in feces shortly after defecation suggests that the feces is an important habitat for these organisms, and horse fecal samples that were improperly stored can be identified by presence of bloom taxa.

Aims: To better understand the role of PueA and PueB from Pseudomonas chlororaphis in polyurethane degradation, the present study was conducted to create insertional mutants in their respective genes. Methods and Results: Growth kinetic studies showed that the pueA knockout mutant had a greater effect than the pueB knockout mutant. The pueA mutant had an 80% decrease in cell density from that of the wild type, while the pueB mutant had an 18% decrease in cell density. Polyurethane utilization followed Michaelis-Menten kinetics. The pueA and pueB mutants exhibited a 17% and 10% decrease respectively in growth rate using polyurethane when compared with the wild type. Conclusions: In this present study, pueA and pueB, are shown to be part of an ABC transporter gene cluster that consists of seven open reading frames. Mutational analysis results suggest that PueA may play a more major role in polyurethane degradation than PueB based on cell density and growth rates. Significance and Impact of the Study: The results from this study provide a starting point for the eventual enhancement and bioremediation of polyurethane waste. Understanding the role of polyurethane-degrading enzymes is useful for the creation of strains for this purpose.

Preeclampsia (PE) is a hypertensive disorder that impacts 2–8% of pregnant women worldwide. It is characterized by new onset hypertension during the second half of gestation and is a leading cause of maternal and fetal morbidity/mortality. Maternal obesity increases the risk of PE and is a key predictor of childhood obesity and potentially offspring cardiometabolic complications in a sex‐dependent manner. The influence of the maternal obesogenic environment, with superimposed PE, on offspring development into adulthood is unknown. Obese BPH/5 mice spontaneously exhibit late‐gestational hypertension, fetal demise and growth restriction, and excessive gestational weight gain. BPH/5 females have improved pregnancy outcomes when maternal weight loss via pair‐feeding is imposed beginning at conception. We hypothesized that phenotypic differences between female and male BPH/5 offspring can be influenced by pair feeding BPH/5 dams during pregnancy. BPH/5 pair‐fed dams have improved litter sizes and increased fetal body weights. BPH/5 offspring born to ad libitum dams have similar sex ratios, body weights, and fecal microbiome as well as increased blood pressure that is reduced in the dam pair‐fed offspring. Both BPH/5 male and female offspring born to pair‐fed dams have a reduction in adiposity and an altered gut microbiome, while only female offspring born to pair‐fed dams have decreased circulating leptin and white adipose tissue inflammatory cytokines. These sexually dimorphic results suggest that reduction in the maternal obesogenic environment in early pregnancy may play a greater role in female BPH/5 sex‐dependent cardiometabolic outcomes than males. Reprograming females may mitigate the transgenerational progression of cardiometabolic disease.