Post‐translation modification in A rchaea: lessons from H aloferax volcanii and other haloarchaea

As an ever‐growing number of genome sequences appear, it is becoming increasingly clear that factors other than genome sequence impart complexity to the proteome. Of the various sources of proteomic variability, post‐translational modifications ( PTM s) most greatly serve to expand the variety of proteins found in the cell. Likewise, modulating the rates at which different proteins are degraded also results in a constantly changing cellular protein profile. While both strategies for generating proteomic diversity are adopted by organisms across evolution, the responsible pathways and enzymes in A rchaea are often less well described than are their eukaryotic and bacterial counterparts. Studies on halophilic archaea, in particular H aloferax volcanii , originally isolated from the D ead S ea, are helping to fill the void. In this review, recent developments concerning PTM s and protein degradation in the haloarchaea are discussed.