Volume 2 Issue 12, December 2017

The 2017 Nobel Prize in Chemistry was awarded to Jacques Dubochet, Richard Henderson and Joachim Frank for the development of cryo-electron microscopy, a technique for high-resolution structural determination of biomolecules in solution that has provided unprecedented insight into the biology of microorganisms.

The use of levulinic acid in bioconversion strategies has been limited by the lack of information on the pathways used by microorganisms to degrade it. Now, functional genomics reveals the essential steps for utilization of levulinic acid in Pseudomonas putida.

Recent work finds that reactive oxygen species are generated in cells starved for the nucleobase thymine and contribute to DNA-destructive “thymineless death” mechanisms, which underlie the activities of many drugs, including trimethoprim and sulfa-based antibiotics. Such mechanisms may also apply to cells across the tree of life.

The incorporation of additional gene circuits into hosts can often lead to unpredicted and undesirable behaviours. Recent work has developed a modelling framework that accounts for host–circuit interactions and can predict a variety of phenotypes at both single-cell and population levels.

The cell tropism of noroviruses in vivo remains unclear. Here, the dominant cellular targets during acute norovirus infection of immunocompetent mice are shown to be macrophages, dendritic cells, B cells and T cells in the GALT gut-associated lymphoid tissue.

Structural illumination of host glycan interaction in the evolution and host adaptation of the Salmonella typhoid toxin.

Reactive oxygen species, most likely spawned from dietary-induced fatty acid β-oxidation, directly impact Plasmodium survival inside hepatocytes and sigificantly reduce liver infection.

In situ sampling reveals that members of the SAR11 clade show significantly lower retention by mucous filter feeders, and that this is probably due to their reduced hydrophobic cell surface, suggesting that cell surface properties are important factors in predator–prey interactions.

The crystal structure of MlaA, coupled with simulations of its interaction with phospholipids, elucidates how this outer membrane lipoprotein acts as a phospholipid translocation channel to maintain the asymmetric composition of the outer membrane.

Levulinic acid (LA) is a value-added chemical easily obtained from biomass. The pathway enabling LA degradation in Pseudomonas putida requires five enzymes and can be engineered into Escherichia coli, which could enable further biotechnological applications.

Under nutritional limitation, modification of the Lactobacillus plantarum cell wall by d-alanylation of teichoic acids is important for host intestinal peptidase expression and consequently growth of the Drosophila host, providing further insights into host–commensal interactions.

Fluorescent d-amino acid incorporation reveals host–prey cell wall modification during Bdellovibrio bacteriovorus predation including pore formation and l,d-transpeptidase-mediated prey strengthening.

An integrative modelling framework is developed to predict the behaviours of synthetic circuits and theirimpacts on host physiology.

Thymine starvation generates single-stranded DNA regions and reactive oxygen species, leading to DNA breakage and cell death.

Comparative genomics and high-resolution mass spectrometry reveal the biosynthetic gene clusters, and vast chemical diversity of natural products that they encode, in Photorhabdus and Xenorhabdus, bacteria that interact with hosts as symbionts and entomopathogens.

An atomic model for a type 2 secretion system pseudopilus from Klebsiella oxytoca reveals a comprehensive network of inter-subunit contacts while mutational and functional analyses highlight the role of calcium in PulG folding and stability.