RESUMO
The ribonucleoprotein enzyme ribonuclease P (RNase P) processes tRNAs by cleavage of precursor-tRNAs. RNase P is a ribozyme: The RNA component catalyzes tRNA maturation in vitro without proteins. Remarkable features of RNase P include multiple turnovers in vivo and ability to process diverse substrates. Structures of the bacterial RNase P, including full-length RNAs and a ternary complex with substrate, have been determined by X-ray crystallography. However, crystal structures of free RNA are significantly different from the ternary complex, and the solution structure of the RNA is unknown. Here, we report solution structures of three phylogenetically distinct bacterial RNase P RNAs from Escherichia coli, Agrobacterium tumefaciens, and Bacillus stearothermophilus, determined using small angle X-ray scattering (SAXS) and selective 2'-hydroxyl acylation analyzed by primer extension (SHAPE) analysis. A combination of homology modeling, normal mode analysis, and molecular dynamics was used to refine the structural models against the empirical data of these RNAs in solution under the high ionic strength required for catalytic activity.
Assuntos
RNA Bacteriano/química , Ribonuclease P/química , Agrobacterium tumefaciens/enzimologia , Sítios de Ligação , Catálise , Escherichia coli/enzimologia , Geobacillus stearothermophilus/enzimologia , Conformação de Ácido Nucleico , RNA Bacteriano/metabolismo , RNA Catalítico , RNA de Transferência/química , RNA de Transferência/metabolismo , Ribonuclease P/metabolismo , Espalhamento a Baixo Ângulo , Soluções , Especificidade por SubstratoRESUMO
Introduction: Diabetes poses a global health challenge, giving rise to various complications, including diabetic foot ulcers (DFUs). DFUs, marked by ischemic ulcers susceptible to infection and amputation, underscore the urgency for innovative treatments. This study investigated the impact of photobiomodulation therapy (PBT) and autologous platelet gel (APG) on DFUs recovery. Methods: We systematically searched Web of Science, EMBASE, MEDLINE, Cochrane Library, Scopus, and Google Scholar (2015-2023) by using pertinent terms like "photobiomodulation therapy," "low level light therapy," and "platelet gel." After meticulous data extraction and review, 57 articles were chosen and categorized. Among these, three randomized controlled trials involving 186 participants were selected for APG analysis. Results: Findings demonstrate that APG application carries minimal risk and offers promising improvements in healing time, grade, pain reduction, and granulation tissue formation. Similarly, diverse PBT modalities involving distinct probes and wavelengths exhibit the potential to enhance tissue perfusion, expedite healing, and impede wound progression, reducing the need for invasive interventions. Conclusion: PBT and APG emerge as valuable tools to augment wound healing, mitigate inflammation, and avert amputation, representing compelling therapeutic options for DFUs.