Molecular Biology and Physiology
- Research Article | Molecular Biology and PhysiologyCoexistence of Communicating and Noncommunicating Cells in the Filamentous Cyanobacterium Anabaena
Multicellularity is found in bacteria as well as in eukaryotes, and the filamentous heterocyst-forming (N2-fixing) cyanobacteria represent a simple and ancient paradigm of multicellular organisms. Multicellularity generally involves cell-cell adhesion and communication.
- Research Article | Molecular Biology and PhysiologyPhosphorylation of the Canonical Histone H2A Marks Foci of Damaged DNA in Malaria Parasites
Plasmodium falciparum is the deadliest human parasite that causes malaria when it reaches the bloodstream and begins proliferating inside red blood cells, where the parasites are particularly prone to DNA damage. The molecular mechanisms that allow these pathogens to maintain their genome integrity under such conditions are also the driving force for acquiring genome...
- Research Article | Molecular Biology and PhysiologyCoexpression of MmpS5 and MmpL5 Contributes to Both Efflux Transporter MmpL5 Trimerization and Drug Resistance in Mycobacterium tuberculosis
It has been reported that mycobacterial membrane protein large 5 (MmpL5), a resistance-nodulation-division (RND)-type inner membrane transporter in Mycobacterium tuberculosis (Mtb), is involved in the transport of antimycobacterial drugs. However, the functional roles of the membrane fusion protein mycobacterial membrane protein small 5 (MmpS5), organized as...
- Research Article | Molecular Biology and PhysiologyThe Two-Component System CopRS Maintains Subfemtomolar Levels of Free Copper in the Periplasm of Pseudomonas aeruginosa Using a Phosphatase-Based Mechanism
Copper is a micronutrient required as cofactor in redox enzymes. When free, copper is toxic, mismetallating proteins and generating damaging free radicals.
- Research Article | Molecular Biology and PhysiologyCrucial Role of ppGpp in the Resilience of Escherichia coli to Growth Disruption
The capacity of microbes to resist and overcome environmental insults, known as resilience, allows them to survive in changing environments but also to resist antibiotic and biocide treatments and immune system responses. Although the role of the stringent response in bacterial resilience to nutritional stresses has been well studied, little is known about its importance in the ability of the bacteria to not just resist but also recover...
- Research Article | Molecular Biology and PhysiologyAnalysis of Serial Multidrug-Resistant Tuberculosis Strains Causing Treatment Failure and Within-Host Evolution by Whole-Genome Sequencing
Few studies have focused on the reasons for the low cure rate of multidrug-resistant tuberculosis in China and within-host evolution during treatment, which is of great significance for improving clinical treatment regimens. Acquired resistance events were common during the ineffective treatment, among which resistance to amikacin and high-level moxifloxacin were the most common.
- Research Article | Molecular Biology and PhysiologyHaloferax volcanii Immersed Liquid Biofilms Develop Independently of Known Biofilm Machineries and Exhibit Rapid Honeycomb Pattern Formation
This first molecular biological study of archaeal immersed liquid biofilms advances our basic biological understanding of the model archaeon Haloferax volcanii. Data gleaned from this study also provide an invaluable foundation for future studies to uncover components required for immersed liquid biofilms in this haloarchaeon and also potentially for liquid biofilm...
- Research Article | Molecular Biology and PhysiologyThe Polyphosphate Kinase of Escherichia coli Is Required for Full Production of the Genotoxin Colibactin
Colibactin-producing E. coli induces DNA damage in eukaryotic cells and promotes tumor formation in mouse models of intestinal inflammation. Recent studies have provided strong evidence supporting the causative role of colibactin in human colorectal cancer (CRC) progression.
- Research Article | Molecular Biology and PhysiologyEnzymatic Analysis of Yeast Cell Wall-Resident GAPDH and Its Secretion
Eukaryotic cells secrete many proteins, including many proteins that do not follow the classical secretion pathway. Among these, the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is unexpectedly found in the walls of yeasts and other fungi and in extracellular space in mammalian cell cultures.
- Research Article | Molecular Biology and PhysiologySuppressor Mutations in Type II Secretion Mutants of Vibrio cholerae: Inactivation of the VesC Protease
Genome-wide transposon mutagenesis has identified the genes encoding the T2SS in Vibrio cholerae as essential for viability, but the reason for this is unclear. Mutants with deletions or insertions in these genes can be isolated, suggesting that they have acquired secondary mutations that suppress their growth defect.