Friday, July 21, 2017
Proteomics of white button mushrooms post-harvest
I honestly started reading this paper
because I was 12% awake and the main question I had was something like...
If I'd stopped at the abstract, I'd have known that this group is interested in finding biomarkers that will enable them to select for mushrooms that have enhanced shelf life! As my espresso is being absorbed, this seems like a better idea. I imagine as someone is selectively breeding mushrooms they are probably first focusing on obvious phenotypes like size and shape, but how long that mushroom will last on the shelf might be a lot more problematic to test for at the farm.
Off topic: Did you know that portabello and white button mushrooms are all the same species? Just different stages in the maturation process? 5.1 million fungi species on this planet, and in my country we essentially eat just one of them...maybe this is where I should put the Catbug picture I used above....
Back to the paper! They get a bunch of mushrooms post-harvest and drop them into liquid nitrogen and manually grind the tissue into powder and extract the proteins/peptides in an undisclosed manner. The tryptic peptides are labeled with 4-plex isobaric tags and an online 2D-LC/MS method is used following a protocol in a paper that is not open access. Data is processed with Protein Pilot and Mascot using manufacturer settings.
In the end they obtain 5,878 peptides that correspond to around 1,000 proteins. Over 250 proteins change post-harvest across the datasets. Surprisingly, about 100 proteins are up-regulated! Naively, I assumed that everything would be degradation post-cell death.
The authors pick a few proteins that are shared between the multiple time points and about half of them appear to match via RT-PCR.