Whole-cell modeling predicts alternative proteome allocation strategies in the archaeon Methanococcus maripaludis

Abstract

The archaeon Methanococcus maripaludis (M. maripaludis) is a model organism for studying archaeal physiology and energy conservation in the hydrogenotrophic methanogenesis pathway. M. maripaludis has a distinct proteome allocation strategy, in which ribosomal proteome allocations do not change with growth rates. Here, we developed a proteome-constrained metabolic model that can explain this different proteome allocation strategy. First, we used multiple bioinformatics databases to compile information about the translational process and enzymatic complexes. We then extended a genome-scale metabolic model of M. maripaludis with protein synthesis processes, including ribosome assembly, tRNA charging, and enzyme assembly reactions. The proposed model predicts alternative proteome resource allocation strategies and mutant fitness for this archaeon under different conditions. Therefore, our model provides a framework for studying the effects of resource allocation on the hydrogenotrophic methanogenesis pathway.