Discovery of novel enzyme genes involved in the conversion of an arylglycerol-β-aryl ether metabolite and their use in generating a metabolic pathway for lignin valorization

Microbial conversions known as “biological funneling” have attracted attention for their ability to upgrade heterogeneous mixtures of low-molecular-weight aromatic compounds obtained by chemical lignin depolymerization. β-hydroxypropiovanillone (HPV) and its analogs can be obtained by chemoselective catalytic oxidation of lignin using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone/tert-butyl nitrite/O2, followed by cleavage of arylglycerol-β-aryl ether with zinc. Sphingobium sp. strain SYK-6 can degrade HPV generated by the catabolism of arylglycerol-β-aryl ether through 2-pyrone-4,6-dicarboxylate (PDC), a promising platform chemical. Therefore, production of PDC from HPV can be achieved using the HPV catabolic pathway. However, the pathway and genes involved in the catabolism of vanilloyl acetic acid (VAA) generated during HPV catabolism have not been investigated. In the present study, we isolated SLG_24960 (vceA), which encodes an enzyme that converts VAA into a coenzyme A (CoA) derivative of vanillate (vanilloyl-CoA) from SYK-6, by shotgun cloning. The analysis of a vceA mutant indicated that this gene is not required for VAA conversion in vivo, but it encodes a major enzyme catalyzing CoA-dependent VAA conversion in vitro. We also identified SLG_12450 (vceB), whose product can convert vanilloyl-CoA to vanillate. Enzyme genes besides vceA and vceB, which are necessary for the conversions of HPV to VAA and of vanillate to PDC, were introduced and expressed in Pseudomonas putida. The resulting engineered strain completely converted 1 mM HPV into PDC after 24 h. Our results suggest that the enzyme genes that are not required for the catabolic pathway in microorganisms but can be used for the conversion of target substrates are buried in microbial genomes. These genes are, thus, useful for designing metabolic pathways to produce value-added metabolites.PostprintPeer reviewe

Possible favorable lifestyle changes owing to the coronavirus disease 2019 (COVID-19) pandemic among middle-aged Japanese women: An ancillary survey of the TRF-Japan study using the original "Taberhythm" smartphone app.

Coronavirus disease 2019 (COVID-19) has had a global effect on people's lifestyles. Many people have become physically inactive and developed irregular eating patterns, which leads to unhealthier lifestyles and aggravation of lifestyle-related diseases; these in turn increase the severity of COVID-19. Prior to the COVID-19 pandemic, we developed a smartphone application called "Taberhythm" to investigate eating patterns, physical activity, and subjective feelings of happiness. We aimed to compare lifestyle data before and during the first phase of the COVID-19 pandemic to objectively assess lifestyle changes during quarantine. A total of 464 smartphone users (346 women, 35 ± 12 years old, body mass index [BMI] 23.4 ± 4.5) participated in Period A (January 7 to April 28, 2019) and 622 smartphone users (533 women, 32 ± 11 years old, BMI 23.3 ± 4.0) participated in Period B (January 6 to April 26, 2020). Compared with Period A, there was a sharp decline in physical activity during Period B (4642 ± 3513 vs. 3814 ± 3529 steps/day, p<0.001), especially during the final 9 weeks in both periods (4907 ± 3908 vs. 3528 ± 3397 steps/day, p<0.001); however, there were large variations in physical activity among participants. We found a surprising trend during Period B toward increased happiness among women aged 30-50 years, the group most affected by stay-at-home policies that led to working from home and school closure. Moreover, daily eating duration declined in this population. Additionally, there was a positive association of happiness with steps per day in Period B (ρ = 0.38, p = 0.02). Despite the many negative effects of the COVID-19 pandemic, subjective feelings of happiness among middle-aged Japanese women tended to increase, which indicates that some favorable lifestyle changes that could be adopted during quarantine in the ongoing COVID-19 pandemic

Determination of the Orbital Polarization in YTiO3 by Using Soft X-Ray Linear Dichroism

We report measurements of linear dichroism in x-ray absorption at Ti L2;3 edges of a Mott-insulating ferromagnet YTiO3, where orbital ordering occurs in the triply degenerate Ti 3d t2g states. Dichroic spectra and their integrated intensities are obtained for the incident electric field with polarizations parallel to a, b, and c axes. The comparison of the spectra with atomic multiplet calculations removes the ambiguity about the orbital polarization, i.e., the relative weights of |xy>, |yz>, and |zx> orbits, which are crucial for the origin of ferromagnetism. The result is consistent with the previous analysis of nuclear magnetic resonance in the Mizokawa-Fujimori scheme