Mutacin 1140 belongs to the epidermin group of lantibiotics. Epidermin class lantibiotics are ribosomally synthesized and posttranslationally modified antibiotics with potent activity against Gram-positive bacteria. In particular, this class is effective at targeting drug-resistant Streptococcus pneumoniae, methicillin-resistant Staphylococcus aureus (MRSA), Mycobacterium tuberculosis, and Clostridium difficile.residue is derived from a decarboxylation of a terminal cysteine that is involved in lanthionine ring formation. Studies on mutacin 1140 have revealed new insight into the structural importance of the C-terminal AviCys residue. A C-terminal carboxyl analogue of mutacin 1140 was engineered. Capping the C-terminal carboxyl group with a primary amine restores bioactivity and affords a novel opportunity to synthesize new analogues. A C-terminal fluorescein-labeled mutacin 1140 analogue traps lipid II into a large lipid II lantibiotic complex, similar to that observed in vivo for the lantibiotic nisin. A C-terminal carboxyl analogue of mutacin 1140 competitively inhibits the activity of native mutacin 1140 and nisin. The presence of a C-terminal carboxyl group prevents the formation of the large lipid II lantibiotic complexes but does not prevent the binding of the lantibiotic to lipid II. IMPORTANCE This study addressed the importance of the C-terminal S-[(Z)-2-aminovinyl]-D-cysteine (AviCys) residue for antibacterial activity. We have learned that the posttranslational modification for making the AviCys residue is presumably important for the lateral assembly mechanism of activity that traps lipid II into a large complex. The C-terminal carboxyl analogue of this class of lantibiotics is agreeable to the addition of a wide variety of substrates. The addition of fluorescein enabled in vivo visualization of the epidermin class of lantibiotics in action. These results are significant because, as we demonstrate, the presence of the AviCys residue is not essential for bioactivity, but, more importantly, the removal of the carboxyl group is essential. The ability to make a C-terminal carboxyl analogue that is modifiable will facilitate the synthesis of novel analogues of the epidermin class of lantibiotics that can be developed for new applications.KEYWORDS lantibiotic, decarboxylation, mutacin 1140, nisin L antibiotics, or lanthionine-containing antibiotics, are characterized by their posttranslational modifications (PTMs) (1). Dehydrations of serine and threonine residues into dehydroalanine and dehydrobutyrine residues, respectively, are a common modification found in lantibiotics. These dehydrated residues can be cyclized with cysteines to form thioether bridges, which are called lanthionines (2, 3). The unmodified lantibiotic is encoded by the gene lanA. The genes for biosynthesis and regulation are generally grouped together in a biosynthetic gene cluster. In class I lantibiotics, dehydrations are carried out by the dehydratase, LanB. Lanthionine ring formation is catalyzed by LanC. Lantibiotics can ...
Introduction: Arterial tortuosity syndrome (ATS) is an ultra-rare arteriopathy caused by pathogenic biallelic variants in SLC2A10 leading to tortuosity, elongation, and dilation of vessels, and pulmonary artery (PA) stenosis (Fig 1). No studies to date have evaluated the progression of cardiovascular (CV) features, including aortic root (AR) and ascending aorta (AA) dilation. Hypothesis: We hypothesize AR and AA dilation progress similar to other aortopathies with increase dimensions but stable z-scores in childhood. Methods: A retrospective cohort study of patients at our institution with ATS, defined by homozygous or compound heterozygous SLC2A10 mutations with consistent phenotypes, from 2000-2021 was conducted. CV imaging, medications, and interventions were reviewed. AR and AA measurements were collected from echocardiographic reports and z-scores were calculated. Dilation was defined as z-score > +2. Slopes were calculated using mixed linear regression. Results: Six subjects (5 males) aged 1 month-16 years at diagnosis were included. All had AR dilation, 50% had AA dilation, and 50% had main or branch PA stenosis at a given point. CV intervention was only performed in 1 patient who underwent multiple bilateral PA angioplasties and stenting for severe distal branch PA hypoplasia. Three patients were prescribed beta-blockers, of whom one was also prescribed losartan. Figure 2 shows mean slopes for AR and AA changes. No patients had aortic dissection or CV surgery. Conclusions: In conclusion, AR and AA dilation persist in ATS but with stable z-scores similar to other aortopathies. Larger sample size investigations may further elucidate the role of medications in ATS.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.