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Plastics are ubiquitous in our ecosystems, and microplastic accumulation in the environment is an emerging global health concern. Since available recycling technologies are not economically competitive with primary plastic production, global use is expected to reach 1231 megatons by 2060, with 493 megatons leeching into the environment each year. To identify new nylon-recycling biotechnologies, targeted genome mining was used to identify thermostable enzymes capable of degrading polyamides. Here, we describe the characterization of a novel protein sourced from Thermovenabulum gondwanense: TvgC. TvgC is extremely stable, exhibiting a melting temperature of 93 °C and no detectable losses in hydrolytic activity after one week at 60 °C. While nylonases primarily process nylon-6, TvgC catalysed the degradation of both nylon-6 and nylon-6,6 films, which are considerably more difficult to degrade. Finally, conversion experiments demonstrate that TvgC achieves a 1.2 wt % conversion of nylon-6 film, comparable to that of the most highly engineered nylonases. This novel hyperthermostable protein represents an excellent starting point for future engineering of increasingly efficient nylonases., (© 2024 The Author(s). Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Flavonoids, known for their neuroprotective properties, are abundant in Acacia catechu and Scutellaria baicalensis. Yet, human studies on their combined effects are limited., Objective: This study evaluated the cognitive effects of combined Acacia catechu and Scutellaria baicalensis supplementation in healthy adults., Methods: In a randomized, double-blind, placebo-controlled trial, 26 males and 59 females ( N  = 85; 43 ± 8 yrs) consumed the test product (TP) containing 240 mg stem extract of Scutellaria baicalensis and 51 mg heartwood extract of Acacia catechu (UP326, Unigen, Tacoma, WA USA) or placebo (PLA) for four weeks. Cognitive function and biomarkers were assessed throughout the study., Results: Significant time effects ( p  < 0.001) were observed across cognitive function assessments, with no differences between groups. Energy and fatigue reports showed a significant time effect ( p  = 0.023), while no significant differences emerged in general health and well-being scores. Cortisol levels increased significantly over time across conditions ( p  = 0.005), but no significant changes were observed in change scores or individual visits. Interim ( p  = 0.023) and final ( p  = 0.004) absolute basophil levels differed significantly between groups, with no intergroup changes. No significant differences in BDNF, CRP, or health and safety biomarkers were detected between supplemental conditions or over time., Discussion: Four-week daily TP supplementation significantly enhanced cognitive function without difference from placebo. However, no adverse events or significant blood marker changes were noted, suggesting TP supplementation is generally well-tolerated. Further research is warranted to explore the preventive and attenuating cognitive effects of this supplementation. Trial registration: ISRCTN.org identifier: ISRCTN16548309.

Baeyer-Villiger monooxygenases (BVMOs) are NAD(P)H-dependent flavoproteins that convert ketones to esters and lactones. While these enzymes offer an appealing alternative to traditional Baeyer-Villiger oxidations, these proteins tend to be either too unstable or exhibit too narrow of a substrate scope for implementation as industrial biocatalysts. Here, sequence similarity networks were used to search for novel BVMOs that are both stable and promiscuous. Our genome mining led to the identification of an enzyme from Chloroflexota bacterium (strain G233) dubbed ssnBVMO that exhibits i) the highest melting temperature of any naturally sourced BVMO (62.5 °C), ii) a remarkable kinetic stability across a wide range of conditions, similar to those of PAMO and PockeMO, iii) optimal catalysis at 50 °C, and iv) a broad substrate scope that includes linear aliphatic, aromatic, and sterically bulky ketones. Subsequent quantitative assays using propiophenone demonstrated >95 % conversion. Several fusions were also constructed that linked ssnBVMO to a thermostable phosphite dehydrogenase. These fusions can recycle NADPH and catalyze oxidations with sub-stoichiometric quantities of this expensive cofactor. Characterization of these fusions permitted identification of PTDH-L1-ssnBVMO as the most promising protein that could have utility as a seed sequence for enzyme engineering campaigns aiming to develop biocatalysts for Baeyer-Villiger oxidations., (© 2024 The Authors. ChemBioChem published by Wiley-VCH GmbH.)

Compared with notifiable disease surveillance, claims-based algorithms estimate higher Lyme disease incidence, but their accuracy is unknown. We applied a previously developed Lyme disease algorithm (diagnosis code plus antimicrobial drug prescription dispensing within 30 days) to an administrative claims database in Massachusetts, USA, to identify a Lyme disease cohort during July 2000-June 2019. Clinicians reviewed and adjudicated medical charts from a cohort subset by using national surveillance case definitions. We calculated positive predictive values (PPVs). We identified 12,229 Lyme disease episodes in the claims database and reviewed and adjudicated 128 medical charts. The algorithm's PPV for confirmed, probable, or suspected cases was 93.8% (95% CI 88.1%-97.3%); the PPV was 66.4% (95% CI 57.5%-74.5%) for confirmed and probable cases only. In a high incidence setting, a claims-based algorithm identified cases with a high PPV, suggesting it can be used to assess Lyme disease burden and supplement traditional surveillance data.