Pooja Gupta

Proud to share our latest paper. doi.org/10.1016/j.cr...

Through the dedication of @glynnca.bsky.social and @cryingem.bsky.social we report a thorough method to image molecular organisation within hippocampus tissue.

Structural biology in tissue is well and truly here!

@rosfrankinst.bsky.social

Structurally heterogeneous ribosomes cooperate in protein synthesis in bacterial cells - Nature Communications Cells can simultaneously produce structurally dissimilar ribosomes, suggesting functional specialization of distinct ribosome populations. Here, the authors show that distinct ribosomes cooperate rath...

New cryo-EM/ET story - a brilliant collaboration with Sergey Melnikov's lab in Newcastle @sergeymelnikov.bsky.social and Stefan Pfeffer's lab in Heidelberg @pfeffercryolab.bsky.social. Great work in particular by Karla Helena-Bueno and @sophiekopetschke.bsky.social

www.nature.com/articles/s41...

Really enjoyed the book and the Rethink episode on big tech stealing our lives, I'm sorry this has happened. Goes on to show that for all the chat about AI replacing human creativity, the truth is that AI will degenerate without a constant supply of human creative output!

Awh thanks Jamie! 😁

4 years of serious sleuthing with @jnb-lab.bsky.social and our great collaborators who are not yet on Bluesky have led to a story that kept us guessing throughout - we hope you enjoy reading the paper! :) End/

...reductive pressure that builds because the aa3 oxidases are slowed down by a high membrane potential. Yth is able to reduce O2 regardless. Its deletion slowing rehydration is the first genetic evidence linking germination and bioenergetics since the 60s-70s when these investigations began 8/

...replacing the canonical enzymes YumB instead of NDH-2, and YthAB instead of CydAB, a bd oxidase. A bd oxidase in an aerobic species cultivated with plenty of oxygen was rather surprising given their reputation as O2-scavenging enzymes. Yth in germinating spores serves as a relief valve for... 7/

...a recasting of germination as rehydration *and re-energisation* of a dormant spore. I'll end with a short note on the spore respiratory chain. It has to operate in a membrane with reduced fluidity and at a physiological extreme/edge of life. It has 2 spore-specific isoforms... 6/

This matters because the current view is bioenergetics are only resumed once the spore is fully hydrated, which means processes early in germination cannot be powered as there is no energy. But now, there's energy and so there's room for active transport, macromolecular synthesis and... 5/

The signalling kinetics are faster without O2 as more nutrient is available for receptor activation. The kinetics can be slowed down by deletion of a spore specific bd oxidase in the respiratory chain (more on this later) - hence the signalling is semi-dependent on bioenergetics 4/

Well, we show that basically there are two processes that occur semi-independently in germinating spores: a signalling pathway that alerts the spore to nutrient availability and triggers rehydration, and nutrient-driven bioenergetics - both start simultaneously. 3/

Spores are known to be energetically depleted, so the question is whether they need to restart energetics to be able to germinate (is germination an active process)? Germination (decrease in optical density as spores rehydrate) can be initiated with non-nutrient salts and without O2, so no? 2/

The preprint is out now - we describe how Bacillus spores restart energy metabolism as they exit dormancy! Dormant spores are dehydrated, very robust for long periods, but when they sense nutrient availability, they can germinate rapidly to make the most of the favourable environmental conditions 1/