A multiple regression assessment of the biomineral urease activity from urine drainpipes of California public restrooms

Clogging and odor is strongly associated with ureolytic biomineralization in waterless and low-flow urinal drainage systems in high usage settings. These blockages continue to hinder widespread waterless and low-flow urinal adoption due to subsequent high maintenance requirements and hygiene concerns. Through field observations, hypothesis testing, and multiple regression analysis, this study attempts to characterize, for the first time, the ureolytic activity of the biomineralization found in alternative technologies located at 9 State-owned restrooms. Multiple regression analysis (n = 55, df = 4, R2 = 0.665) suggests that intrasystem sampling location ($$ \hat{\upbeta} $$ β ̂ = 1.23, p < 0.001), annual users per rest area ($$ \hat{\upbeta} $$ β ̂ = 0.5, p = 0.004), and the volatile solids to total solids mass fraction ($$ \hat{\upbeta} $$ β ̂ = 0.59, p = 0.003), are statistically significant influencers of the ureolytic activity of biomineral samples (p < 0.05). Conversely, ureC gene abundance (p = 0.551), urinal type (p = 0.521) and sampling season (p = 0.956) are not significant predictors of biomineral ureolytic activity. We conclude that high concentrations of the urease alpha subunit, ureC, which can be interpreted as proxy measure of a strong, potentially ureolytic community, does not necessarily mean that the gene is being expressed. Future studies should assess ureC transcriptional activity to measure gene expression rather than gene abundance to assess the relationship between environmental conditions, their role in transcription, and urease activities. In sum, this study presents a method to characterize biomineral ureolysis. This study establishes baseline values for future ureolytic inhibition treatment studies that seek to improve the usability of urine collection and related source separation technologies.

Gut bacterial tyrosine decarboxylase associates with clinical variables in a longitudinal cohort study of Parkinsons disease

Gut microbiota influences the clinical response of a wide variety of orally administered drugs. However, the underlying mechanisms through which drug–microbiota interactions occur are still obscure. Previously, we reported that tyrosine decarboxylating (TDC) bacteria may restrict the levels of levodopa reaching circulation in patients with Parkinson’s disease (PD). We observed a significant positive association between disease duration and the abundance of the bacterial tdc-gene. The question arises whether increased exposure to anti-PD medication could affect the abundance of bacterial TDC, to ultimately impact drug efficacy. To this end, we investigated the potential association between anti-PD drug exposure and bacterial tdc-gene abundance over a period of 2 years in a longitudinal cohort of PD patients and healthy controls. Our data reveal significant associations between tdc-gene abundance, several anti-PD medications, including entacapone, rasagiline, pramipexole, and ropinirole but not levodopa, and gastrointestinal symptoms, warranting further research on the effect of anti-PD medication on microbial changes and gastrointestinal function.

Determination of Butyrate Synthesis Capacity in Gut Microbiota: Quantification of but Gene Abundance by qPCR in Fecal Samples

Butyrate is formed in the gut during bacterial fermentation of dietary fiber and is attributed numerous beneficial effects on the host metabolism. We aimed to develop a method for the assessment of functional capacity of gut microbiota butyrate synthesis based on the qPCR quantification of bacterial gene coding butyryl-CoA:acetate CoA-transferase, the key enzyme of butyrate synthesis. In silico, we identified bacteria possessing but gene among human gut microbiota by searching but coding sequences in available databases. We designed and validated six sets of degenerate primers covering all selected bacteria, based on their phylogenetic nearness and sequence similarity, and developed a method for gene abundance normalization in human fecal DNA. We determined but gene abundance in fecal DNA of subjects with opposing dietary patterns and metabolic phenotypes—lean vegans (VG) and healthy obese omnivores (OB) with known fecal microbiota and metabolome composition. We found higher but gene copy number in VG compared with OB, in line with higher fecal butyrate content in VG group. We further found a positive correlation between the relative abundance of target bacterial genera identified by next-generation sequencing and groups of but genecontaining bacteria determined by specific primers. In conclusion, this approach represents a simple and feasible tool for estimation of microbial functional capacity.

Stronger effect of maize rhizosphere than phosphorus fertilization on soil phosphatase activity and associated bacterial communities in acidic soil: distinct influences on phoC- and phoD-harboring bacteria

Aims The bacteria phoC and phoD genes encode acid and alkaline phosphatase (ACP and ALP), respectively, which mineralize organic phosphorus (P) to inorganic P. The relative importance of P fertilization and the plant rhizosphere on soil phosphatase activities and associated bacterial communities in acidic soils are poorly understood; whether phoC- and phoD-harboring bacterial communities display different responses remains undetermined. Methods Maize was grown in acidic soil supplemented with 0 (P0), 20 (P20), and 200 (P200) mg P2O5 kg− 1 for 42 days. Maize biomasses, plant nutrients, soil properties, phosphatase activities, and associated bacterial abundance and community composition were determined. Results Relative to bulk soils, rhizosphere showed increased ACP and ALP activities, phoC and phoD gene abundance, but these effects were reduced in strength with P200 treatment, except for phoC gene abundance. The rhizosphere effect increased α-diversity of phoC-harboring bacteria under P fertilization but reduced α-diversity of phoD-harboring bacteria under P0 and P20 treatments. The rhizosphere significantly influenced both phoC- and phoD-harboring bacterial community compositions, with stronger effect on phoD-harboring bacteria; while P fertilization affected phoD-harboring bacteria but not phoC-harboring bacteria. Immigrated and extinct species play important roles in reshaping phoC- and phoD-harboring bacterial communities, respectively, in response to the rhizosphere effect. Conclusions Compared with P fertilization, the maize rhizosphere more strongly influenced soil phosphatase activities and phoC- and phoD-harboring bacterial communities in acidic soils, with phoD-harboring bacteria responding more strongly to the rhizosphere effect and P fertilization. Notably, the strength of the rhizosphere effect heavily relied on P fertilization level.

Gut bacterial tyrosine decarboxylase gene abundance associates with disease duration, medication exposure, and gastrointestinal symptoms in a longitudinal cohort of Parkinson's disease patients.

Gut microbiota influences the clinical response of a wide variety of orally administered drugs. However, the underlying mechanisms by which drug-microbiota interactions occur are still obscure. Previously, we reported that tyrosine decarboxylating (TDC) bacteria may restrict the levels of levodopa reaching the circulation in patients with Parkinson's disease (PD). We observed a significant positive association between disease duration and the abundance of the bacterial tdc-gene. The question arises whether increased exposure to anti-PD medication could affect the abundance of bacterial TDC, to ultimately impact drug efficacy. To this end, we investigated the potential association between anti-PD drug exposure and bacterial tdc-gene abundance over a time period of two years in a longitudinal cohort of PD patients and healthy controls. Our data reveal significant associations between tdc-gene abundance, anti-PD medication, and gastrointestinal symptoms and warrants further research on the effect of anti-PD medication on microbial changes and gastrointestinal-function.