This is a project to investigate a potential biochemical solution to hop creep.
Hop creep is thought to be caused by diastatic enzymes originating from hops during dry hopping (Cottrell, JASBC 2022).
The two primary diastatic enzymes responsible are alpha- and beta-amylase. One possible solution to hop creep would be the use a protease that selectively degrades these two enzymes while leaving foam-active proteins intact. This project investigates if such a proteolytic approach is feasible.
As the proteome of Humulus lupulus is not well annotated, orthologous proteins from the closely related Cannabis sativa must be used for this analysis. These are A0A803QK01 (beta-amylase) and A0A803QQW1 (alpha-amylase). These two proteins are our intended targets for proteolytic degradation.
The major foam-active proteins are thought to be LTP1, protein Z, and various barley hordeins (Hao and Li, JASBC 2006, Blasco et al., Int Microbio 2011). These are annotated as P07597 (LTP1), P06293 (Protein Z), P06470 (B1-hordein), P06471 (B3-hordein), and P06472 (C-hordein). Our ideal protease would not target, or only minimally degrade, these proteins, to ensure that foam formation is not compromised.
First, create the conda environment:
conda env create -f environment.yaml
conda activate hop-creep
Download the latest MySQL MEROPS release and place in data/merops/.
wget https://ftp.ebi.ac.uk/pub/databases/merops/current_release/meropsweb121.tar.gz
mv meropsweb121.tar.gz data/merops/
tar -zxvf data/merops/meropsweb121.tar.gz