Simon writes:
Dear TwiMers,
I would love to hear your take on the paper “Bacterial cGAS-like enzymes synthesize diverse nucleotide signals” from Whiteley et al in Nature. It is a fresh paper that has an UNIMAGINABLE amount of data; each section feels like it probably could be a paper on its own. The conclusions are dramatic and impactful, and the figures are all “scientific Picasso:s”.
Love the show!
E
Ben writes:
Dear TWiM holobionts,
I wanted to see what you thought about the term ‘reduced genome size’ as applied to organisms whose genomes are small due to reliance on other organisms for their survival; such as Rickettsia. The idea that having a small genome is because there’s lots of metabolic processes etc. that you rely on other organisms to perform for you has never set well with me. Many plants have wildly large and complex genomes, but are utterly dependent on yeast and bacterial symbionts for their survival, while us humans could never have survived without our microbes before modern medicine. Should then, we, the plants dependent on symbionts, and the countless number of similar examples, be considered as having reduced genome sizes as they cannot survive without genes that are encoded by their microbes?
It’s a chilly 15°C in Adelaide, South Australia today but 32°C only about 200km northwest, where I grew up!
Hoping you were all safe during Dorian.
Keep up the wonderful work!
—
Ben Liffner
PhD Candidate – Malaria Biology Lab (Wilson Lab)
Research Centre for Infectious Diseases
School of Biological Sciences
The University of Adelaide
Ben writes:
To the TWiM team,
Sorry for the recent bombardment of questions, but I found this one too interesting not to ask.
Molluscs and Arthropods use haemocyanin, rather than haemoglobin, to transport their oxygen. Haemocyanin uses copper to bind rather than iron, and is free floating in the haemolymph rather than packed into red blood cells. It’s thought that the evolutionary reason for this is that in cold waters with low oxygen, copper is more efficient than iron at binding oxygen; but this doesn’t explain why Arthropods that live in warm climates like spiders use haemocyanin.
So my question for the TWiM team is, could haemocyanin have been selected for in warm, oxygen rich, environments due to the antimicrobial effects of ionic copper?
Looking forward to seeing what you all think!
Regards,
Ben
—
Ben Liffner
PhD Candidate – Malaria Biology Lab (Wilson Lab)
Research Centre for Infectious Diseases
School of Biological Sciences
The University of Adelaide