Molecular Biology and Physiology
Research Article | Molecular Biology and PhysiologyMinor Isozymes Tailor Yeast Metabolism to Carbon AvailabilityGene duplication is one of the main evolutionary paths to new protein function. Typically, duplicated genes either accumulate mutations and degrade into pseudogenes or are retained and diverge in function. Some duplicated genes, however, show long-term persistence without apparently acquiring new function. An important class of isozymes consists of those that catalyze the same reaction in the same compartment, where knockout of one...
Research Article | Molecular Biology and PhysiologySystems-Level Analysis of Oxygen Exposure in Zymomonas mobilis: Implications for Isoprenoid ProductionMicrobially generated biofuels and bioproducts have the potential to provide a more environmentally sustainable alternative to fossil-fuel-derived products. In particular, isoprenoids, a diverse class of natural products, are chemically suitable for use as high-grade transport fuels and other commodity molecules. However, metabolic engineering for increased production of isoprenoids and other bioproducts is limited by an incomplete...
Research Article | Molecular Biology and PhysiologyOxidative Pathways of Deoxyribose and Deoxyribonate CatabolismDeoxyribose is one of the building blocks of DNA and is released when cells die and their DNA degrades. We identified a bacterium that can grow with deoxyribose as its sole source of carbon even though its genome does not contain any of the known genes for breaking down deoxyribose. By growing many mutants of this bacterium together on deoxyribose and using DNA sequencing to measure the change in the mutants’ abundance, we identified...
Research Article | Molecular Biology and PhysiologyEmergent Subpopulation Behavior Uncovered with a Community Dynamic Metabolic Model of Escherichia coli Diauxic GrowthEscherichia coli diauxie is a fundamental example of metabolic adaptation, a phenomenon that is not yet completely understood. Further insight into this process can be achieved by integrating experimental and computational modeling methods. We present a dynamic metabolic modeling approach that captures diauxie as an emergent property of subpopulation dynamics in...
Research Article | Molecular Biology and PhysiologyLabel-Free Quantitative Proteomics of Lysine Acetylome Identifies Substrates of Gcn5 in Magnaporthe oryzae Autophagy and Epigenetic RegulationGcn5 is a histone acetyltransferase that was previously shown to regulate phototropic and starvation-induced autophagy in the rice blast fungus Magnaporthe oryzae, likely via modification on autophagy protein Atg7. In this study, we identified more potential substrates of Gcn5-mediated acetylation by quantitative and comparative acetylome analyses. By epifluorescence...
Research Article | Molecular Biology and PhysiologyGenome-Wide Analysis of Transcriptional Changes and Genes That Contribute to Fitness during Degradation of the Anthropogenic Pollutant Pentachlorophenol by Sphingobium chlorophenolicumPhenolic compounds such as pentachlorophenol (PCP), triclosan, and 2,4-dichlorophenoxyacetic acid (2,4-D) represent a common class of anthropogenic biocides. Despite the novelty of these compounds, many can be degraded by microbes isolated from contaminated sites. However, degradation of this class of chemicals often generates toxic intermediates, which may contribute to their recalcitrance to biodegradation. We have addressed the...
Research Article | Molecular Biology and PhysiologyRibosome Profiling Reveals HSP90 Inhibitor Effects on Stage-Specific Protein Synthesis in Leishmania donovaniLeishmania parasites cause severe illness in humans and animals. They exist in two developmental stages, insect form and mammalian form, which differ in shape and gene expression. By mapping and quantifying RNA fragments protected by protein synthesis complexes, we determined the rates of protein synthesis for >90% of all Leishmania proteins in response to the inhibition of a key regulatory protein, the 90-kDa heat...
Research Article | Molecular Biology and PhysiologyArabinose-Induced Catabolite Repression as a Mechanism for Pentose Hierarchy Control in Clostridium acetobutylicum ATCC 824Clostridium acetobutylicum can ferment a wide variety of carbohydrates to the commodity chemicals acetone, butanol, and ethanol. Recent advances in genetic engineering have expanded the chemical production repertoire of C. acetobutylicum using synthetic biology. Due to its natural properties and...
Research Article | Molecular Biology and PhysiologyCharacterization of Aspergillus niger Isolated from the International Space StationA thorough understanding of how fungi respond and adapt to the various stimuli encountered during spaceflight presents many economic benefits and is imperative for the health of crew. As A. niger is a predominant ISS isolate frequently detected in built environments, studies of A. niger strains...
Research Article | Molecular Biology and PhysiologyCoordinated Hibernation of Transcriptional and Translational Apparatus during Growth Transition of Escherichia coli to Stationary PhaseDuring the growth transition of E. coli from exponential phase to stationary, the genome expression pattern is altered markedly. For this alteration, the transcription apparatus is altered by binding of anti-sigma factor Rsd to the RpoD sigma factor for sigma factor replacement, while the translation machinery is modulated by binding of RMF to 70S ribosome to form...