Fig. 4

Responses of metabolic recycling systems to nitrogen stress in M. alpina. Heatmap shows changes in peptides (a) and metabolites (b) involved in nitrogen metabolism (especially amino acid metabolism) during fermentation. c Changes in enzymes involved in ubiquitin mediated proteolysis pathway. d Changes in key enzymes involved in cell autophagy. UBA1, ubiquitin-activating enzyme E1, UBLE1B, ubiquitin-like 1-activating enzyme E1 B, RPN, 26S proteasome regulatory subunit, PSMA, 20S proteasome subunit alpha, PSMB, 20S proteasome subunit beta, ltaE, threonine aldolase, BLMH, bleomycin hydrolase, GAD, glutamate decarboxylase, PCD, 1-pyrroline-5-carboxylate dehydrogenase, rocD, ornithine-oxo-acid transaminase, mTOR, serine/threonine-protein kinase mTOR, Atg, autophagy-relate gene, CDC48, transitional endoplasmic reticulum ATPase, SPH1, UBX domain-containing protein 1, VAC8, vacuolar protein 8, Ypt7, GTP-binding protein