Secret History: Return of the Black Death Channel 4, 7-8pm In 1348 the Black Death swept through London, killing people within days of the appearance of their first symptoms. Exactly how many died, and why, has long been a mystery. This Secret History documentary follows experts as they pick through the evidence and reveal why the plague killed on such a scale. And they ask, what might be coming next?

Medscape

https://limlab.ucsf.edu/papers/pdfs/lsq_2013.pdf

Repurposing CRISPR as an RNA-guided platform for sequence-specific control of gene expression.

Evolution and functions of long noncoding RNAs

The folding of many newly synthesized proteins in the cell depends on a set of conserved proteins known as molecular chaperones. These prevent the formation of misfolded protein structures, both under normal conditions and when cells are exposed to stresses such as high temperature. Significant progress has been made in the understanding of the ATP-dependent mechanisms used by the Hsp70 and chaperonin families of molecular chaperones, which can cooperate to assist in folding new polypeptide chains.

Molecular chaperones in cellular protein folding.

I. the origin of species by means of natural selection

https://www.cell.com/cell/pdf/S0092-8674(12)01546-2.pdf

A Decade of Riboswitches

https://www.cell.com/cell/pdf/S0092-8674(02)01134-0.pdf

Sensing Small Molecules by Nascent RNA: A Mechanism to Control Transcription in Bacteria

The riboswitch control of bacterial metabolism.

Many prokaryotic species generate hydrogen sulfide (H(2)S) in their natural environments. However, the biochemistry and physiological role of this gas in nonsulfur bacteria remain largely unknown. Here we demonstrate that inactivation of putative cystathionine β-synthase, cystathionine γ-lyase, or 3-mercaptopyruvate sulfurtransferase in Bacillus anthracis, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli suppresses H(2)S production, rendering these pathogens highly sensitive to a multitude of antibiotics. Exogenous H(2)S suppresses this effect. Moreover, in bacteria that normally produce H(2)S and nitric oxide, these two gases act synergistically to sustain growth. The mechanism of gas-mediated antibiotic resistance relies on mitigation of oxidative stress imposed by antibiotics.

https://science.sciencemag.org/content/sci/334/6058/986.full.pdf

H2S: a universal defense against antibiotics in bacteria

During transcription of protein-coding genes, bacterial RNA polymerase (RNAP) is closely followed by a ribosome that translates the newly synthesized transcript. Our in vivo measurements show that the overall elongation rate of transcription is tightly controlled by the rate of translation. Acceleration and deceleration of a ribosome result in corresponding changes in the speed of RNAP. Moreover, we found an inverse correlation between the number of rare codons in a gene, which delay ribosome progression, and the rate of transcription. The stimulating effect of a ribosome on RNAP is achieved by preventing its spontaneous backtracking, which enhances the pace and also facilitates readthrough of roadblocks in vivo. Such a cooperative mechanism ensures that the transcriptional yield is always adjusted to translational needs at different genes and under various growth conditions.

/pdf/cooperation-between-translating-ribosomes-and-rna-polymerase-2shlmxbmtm.pdf

Evgeny Nudler

Papers

A Decade of Riboswitches

Sensing Small Molecules by Nascent RNA: A Mechanism to Control Transcription in Bacteria

The riboswitch control of bacterial metabolism.

H2S: a universal defense against antibiotics in bacteria

Cooperation between translating ribosomes and RNA polymerase in transcription elongation.