Two codependent routes lead to high-level MRSA.

Methicillin-resistant (MRSA), in which acquisition of [which encodes the cell wall peptidoglycan biosynthesis component penicillin-binding protein 2a (PBP2a)] confers resistance to β-lactam antibiotics, is of major clinical concern. We show that, in the presence of antibiotics, MRSA adopts an alternative mode of cell division and shows an altered peptidoglycan architecture at the division septum. PBP2a can replace the transpeptidase activity of the endogenous and essential PBP2 but not that of PBP1, which is responsible for the distinctive native septal peptidoglycan architecture.

Maintenance of cell wall remodeling and vesicle production are connected in .

Pathogenic and nonpathogenic mycobacteria secrete extracellular vesicles (EVs) under various conditions. EVs produced by ( ) have raised significant interest for their potential in cell communication, nutrient acquisition, and immune evasion. However, the relevance of vesicle secretion during tuberculosis infection remains unknown due to the limited understanding of mycobacterial vesicle biogenesis.

Mechanism of Action of Oxazoline-Based Antimicrobial Polymers Against Staphylococcus aureus: In Vivo Antimicrobial Activity Evaluation.

Antimicrobial-resistant pathogens have reached alarming levels, becoming one of the most pressing global health issues. Hence, new treatments are necessary for the fight against antimicrobial resistance. Synthetic nanoengineered antimicrobial polymers (SNAPs) have emerged as a promising alternative to antimicrobial peptides, overcoming some of their limitations while keeping their key features.

The Staphylococcus aureus cell division protein, DivIC, interacts with the cell wall and controls its biosynthesis.

Bacterial cell division is a complex, dynamic process that requires multiple protein components to orchestrate its progression. Many division proteins are highly conserved across bacterial species alluding to a common, basic mechanism. Central to division is a transmembrane trimeric complex involving DivIB, DivIC and FtsL in Gram-positives.

Demonstration of the role of cell wall homeostasis in growth and the action of bactericidal antibiotics.

Bacterial cell wall peptidoglycan is essential, maintaining both cellular integrity and morphology, in the face of internal turgor pressure. Peptidoglycan synthesis is important, as it is targeted by cell wall antibiotics, including methicillin and vancomycin. Here, we have used the major human pathogen to elucidate both the cell wall dynamic processes essential for growth (life) and the bactericidal effects of cell wall antibiotics (death) based on the principle of coordinated peptidoglycan synthesis and hydrolysis.

Correlative Super-Resolution Optical and Atomic Force Microscopy Reveals Relationships Between Bacterial Cell Wall Architecture and Synthesis in .

Understanding how bacteria grow and divide requires insight into both the molecular-level dynamics of ultrastructure and the chemistry of the constituent components. Atomic force microscopy (AFM) can provide near molecular resolution images of biological systems but typically provides limited chemical information. Conversely, while super-resolution optical microscopy allows localization of particular molecules and chemistries, information on the molecular context is difficult to obtain.

Rational Design and Self-Assembly of Coiled-Coil Linked SasG Protein Fibrils.

Protein engineering is an attractive approach for the self-assembly of nanometer-scale architectures for a range of potential nanotechnologies. Using the versatile chemistry provided by protein folding and assembly, coupled with amino acid side-chain functionality, allows for the construction of precise molecular "protein origami" hierarchical patterned structures for a range of nanoapplications such as stand-alone enzymatic pathways and molecular machines. The surface protein SasG is a rigid, rod-like structure shown to have high mechanical strength due to "clamp-like" intradomain features and a stabilizing interface between the G5 and E domains, making it an excellent building block for molecular self-assembly.

Insights into the structure and nanomechanics of a quatsome membrane by force spectroscopy measurements and molecular simulations.

Quatsomes (QS) are unilamellar nanovesicles constituted by quaternary ammonium surfactants and sterols in defined molar ratios. Unlike conventional liposomes, QS are stable upon long storage such as for several years, they show outstanding vesicle-to-vesicle homogeneity regarding size and lamellarity, and they have the structural and physicochemical requirements to be a potential platform for site-specific delivery of hydrophilic and lipophilic molecules. Knowing in detail the structure and mechanical properties of the QS membrane is of great importance for the design of deformable and flexible nanovesicle alternatives, highly pursued in nanomedicine applications such as the transdermal administration route.