Both Met(104) and Met(105) are involved, either directly or indirectly, in the redox mediated ligand switch of the heme-dependent transcription factor, RcoM-1. Recent studies of Burkholderia xenovorans RcoM identified Cys(94) as the thiolate ligand in the Fe(III) state of the heme cofactor. Upon reduction, a neutral donor replaces Cys(94) trans to His(74). Homology modelling implicated either Met(104) or Met(105) as the possible ligand in the Fe(II) state. We spectroscopically compared wild type (WT) RcoM-1 to three Met-to-Leu variants (M104L, M105L, and M104L/M105L) to identify which Met residue acts as the ligand. All proteins were isolated as admixtures of Fe(III) and Fe(II)-CO heme; oxidation by ferricyanide enables study of homogeneous oxidation and coordination states. Met(104) is the CO-replaceable Fe(II) heme ligand. The magnetic circular dichroism (MCD) spectrum of Fe(II) M105L resembled WT. M104L and M104L/M105L, however, showed spectra arising from the formation of a high-spin, five-coordinate species indicating the loss of the ligand. The electron paramagnetic resonance (EPR) spectra of WT Fe(III) RcoM-1, oxidized Fe(III) M104L, and as-isolated M105L exhibited narrow, rhombic low-spin signals typical of thiolate-bound hemes. In contrast, oxidized Fe(III) M105L and oxidized Fe(III) M104L/M105L revealed a broad, rhombic low-spin, six-coordinate signal indicative of replacement of the thiolate by a neutral ligand. Thus, we conclude that Met(105) is important to the stability of the Fe(III) heme pocket during oxidation.

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The COVID‐19 pandemic has had devastating effects on Black and rural populations with a mortality rate among Blacks three times that of Whites and both rural and Black populations experiencing limited access to COVID‐19 resources. The primary purpose of this study was to explore the health, financial, and psychological impact of COVID‐19 among rural White Appalachian and Black nonrural central Kentucky church congregants. Secondarily we sought to examine the association between sociodemographics and behaviors, attitudes, and beliefs regarding COVID‐19 and intent to vaccinate. We used a cross sectional survey design developed with the constructs of the Health Belief and Theory of Planned Behavior models. The majority of the 942 respondents were ≥36 years. A total of 54% were from central Kentucky, while 47.5% were from Appalachia. Among all participants, the pandemic worsened anxiety and depression and delayed access to medical care. There were no associations between sociodemographics and practicing COVID‐19 prevention behaviors. Appalachian region was associated with financial burden and delay in medical care (p = 0.03). Appalachian respondents had lower perceived benefit and attitude for COVID‐19 prevention behaviors (p = 0.004 and <0.001, respectively). Among all respondents, the perceived risk of contracting COVID was high (54%), yet 33.2% indicated unlikeliness to receive the COVID‐19 vaccine if offered. The COVID‐19 pandemic had a differential impact on White rural and Black nonrural populations. Nurses and public health officials should assess knowledge and explore patient's attitudes regarding COVID‐19 prevention behaviors, as well as advocate for public health resources to reduce the differential impact of COVID‐19 on these at‐risk populations.

RcoM, a heme-containing, CO-sensing transcription factor, is one of two known bacterial regulators of CO metabolism. Unlike its analogue CooA, the structure and DNA-binding properties of RcoM remain largely uncharacterized. Using a combination of size exclusion chromatography and sedimentation equilibrium, we demonstrate that RcoM-1 from Paraburkholderia xenovorans is a dimer, wherein the heme-binding domain mediates dimerization. Using bioinformatics, we show that RcoM is found in three distinct genomic contexts, in accordance with the previous literature. We propose a refined consensus DNA-binding sequence for RcoM based on sequence alignments of coxM-associated promoters. The RcoM promoter consensus sequence bears two well-conserved direct repeats, consistent with other LytTR domain-containing transcription factors. In addition, there is a third, moderately conserved direct repeat site. Surprisingly, PxRcoM-1 requires all three repeat sites to cooperatively bind DNA with a [P]1/2 of 250 ± 10 nM and an average Hill coefficient, n, of 1.7 ± 0.1. The paralog PxRcoM-2 binds to the same triplet motif with comparable affinity and cooperativity. Considering this unusual DNA binding stoichiometry, that is, a dimeric protein with a triplet DNA repeat-binding site, we hypothesize that RcoM interacts with DNA in a manner distinct from other LytTR domain-containing transcription factors.

The connections between shared personal vehicles of individuals with disabilities (IWDs) and their household family members play an important role in the mobility, overall health, and well-being of all involved actors, yet this topic remains mostly overlooked within publicly available research. Families that include a non-driving IWD are more likely to be low-income, and often struggle with the costs of operating a family car but, due to insufficient public transportation options, they own vehicles despite their prohibitive cost. This exploratory study utilized the Systems Engineering Initiative for Patient Safety (SEIPS) model, a framework focused on assessing the interplaying sociotechnical factors that contribute toward work-systems to gain a holistic understanding of the factors that influence household vehicles, safety, and a sense of well-being for non-driving IWDs and their household family members. A combined effort of surveys, interviews, qualitative coding, and statistical analysis (including one-way ANOVA) revealed a series of influential factors, including: (1) slow bureaucratic processes for vehicle funding; (2) error-prone modifications including lift and tie-downs; (3) miscommunications between IWDs and family members; and (4) residential area development and subsequent social support. Findings highlight the need for improved access to government funding, more reliable modification equipment, and interior vehicle designs that consider better social integration for IWDs.