Polyketide synthases (PKSs) and non-ribosomal peptide synthetases (NRPSs) are large multidomain proteins present in microorganisms that produce bioactive compounds. Curacin A is such a bioactive compound with potent anti-proliferative activity. During its biosynthesis the growing substrate is bound covalently to an acyl carrier protein (ACP) that is able to access catalytic sites of neighboring domains for chain elongation and modification. While ACP domains usually occur as monomers, the curacin A cluster codes for a triplet ACP (ACP(I)-ACP(II)-ACP(III)) within the CurA PKS module. We have determined the structure of the isolated holo-ACP(I) and show that the ACPs are independent of each other within this tridomain system. In addition, we have determined the structure of the 3-hydroxyl-3-methylglutaryl-loaded holo-ACP(I), which is the substrate for the unique halogenase (Hal) domain embedded within the CurA module. We have identified the interaction surface of both proteins using mutagenesis and MALDI-based identification of product formation. Amino acids affecting product formation are located on helices II and III of ACP(I) and form a contiguous surface. Since the CurA Hal accepts substrate only when presented by one of the ACPs within the ACP(I)-ACP(II)-ACP(III) tridomain, our data provide insight into the specificity of the chlorination reaction.
Graph theory has been widely used to quantitatively analyze complex networks of molecules, materials, and cells. Analyzing the dynamic complex structure of extracellular matrix can predict cell-material interactions but has not yet been demonstrated. In this study, graph theory-based mathematical modeling of RGD ligand graph inter-relation is demonstrated by differentially cutting off RGD-to-RGD interlinkages with flexibly conjugated magnetic nanobars (MNBs) with tunable aspect ratio.
Background: This study examined how university students' social media use is related to their mental health (subjective well-being [SWB] and loneliness) and perceived physical health. A cognitive bias model and a social network mediation model were used to compare social capital formed via face-to-face and online communication, considering the effects of personality traits (i.e.
Nonalcoholic fatty liver disease (NAFLD) or metabolic dysfunction-associated steatotic liver disease (MASLD) is a significant global public health dilemma with wide-ranging social and economic implications. Diet and lifestyle modifications remain essential components of NAFLD management. The current study investigated the association between diet-related inflammation and NAFLD among 3110 Iranian adults participating in the Amol Cohort Study (AmolCS), employing the Structural Equation Modeling (SEM) approach.
Background And Objectives: Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome is a maternally inherited mitochondrial disorder that mostly affects the central nervous system and skeletal muscle. This study provides a comprehensive summary of the clinical symptoms, multisystemic pathogenesis, and genetic characteristics of MELAS syndrome. The aim was to improve comprehension of clinical practice and gain a deeper understanding of the latest pathophysiological theories.
Background: To describe the epidemiology and clinical characteristics of migraine and the status of treatment in Colombia. Additionally, the use of health resources by patients was measured.
Methods: This was a non-interventional, retrospective, descriptive study conducted in one Colombian Health Management Organization (HMO) from 2018 to 2022 with a follow-up period of 5 years.
