[favoritecolor]

I love when I see smell research on Hacker News -- and hopefully I can provide a bit of context about this paper.

This finding recently made a big splash at AChemS 2021 (the annual meeting for the Association for Chemoreception Sciences). And it actually is a really big deal. A protein structure is extremely information rich, telling you where all of the atoms of a given protein are (ish). Before this finding, there were NO structures of any olfactory receptor, and historically the publication of the first structure of a given biomolecule has been a watershed moment for that field (insulin, ribosome, many other examples).

What's more, they used the structural information to rationally engineer their olfactory receptor, expanding the binding pocket and changing how the receptor responds to different odorants. That was pretty much impossible to do before this. So, this is a pretty huge finding, and will definitely encourage more structural work on olfactory receptors in the future.

If I had to poke a hole in this finding, it would be that insect olfactory receptors are substantially different from mammalian olfactory receptors. But in my opinion, it seems that the buzz about this paper is definitely justified. Very cool!

[shoto_io]

Is this in any way support for the "Vibration theory of olfaction"?

https://en.wikipedia.org/wiki/Vibration_theory_of_olfaction

[beebeepka]

Thanks to your link, I discovered this: https://en.m.wikipedia.org/wiki/Docking_theory_of_olfaction

Had no idea it's just a theory. I've lived many years "knowing" that we detect smells due to their shapes.

[Duller-Finite]

This paper is the first structure of any odorant receptor-ligand interaction. There's currently no equivalent structure for mammalian odorant receptors to validate the docking theory, but it's likely correct.

[dr_dshiv]

I'm dying because there is some mid 1800s theory of smell that uses vibration and harmony, metaphorically, and I can't find it.

But while searching, I came across this: https://www.bbc.com/news/science-environment-21150046

[jfengel]

Question: does this put an end to Luca Turin's vibration theory?

I realize that this has long been considered crackpottery, and there has never been a reasonable sense of a mechanism for it. But it did seem to offer at least a stab at a couple of questions that didn't have good answers in the ordinary lock-and-key model of olfaction, such as why sulfur-containing molecules all smell "sulfury" if they all unlock different locks.

As far as I can tell the idea sorta just died out. A lot of work was done trying to make odor molecules with different isotopes, with intriguing but inconclusive results.

Still, I've been kinda curious to see if the theory was finally over and done.

[shoto_io]

I referenced to the same theory above. It seems to have died out, again. The idea had a long winter and then came back. Maybe history is repeating.

[dr_dshiv]

Ridiculous that it would be considered crackpottery. It's perfectly reasonable. We all want data, but it is perfectly reasonable

[outworlder]

Do you think that it would be possible to use this research as a basis for artificial smell receptors?

I understand that some kinds exist (and some are even off the shelf) but they tend to be pretty limited in what they can 'sniff'.