Fig. 1
From: Bridging human chaperonopathies and microbial chaperonins
Chaperonins of Group I and II in archaea and humans. Top left: archaeal CCT complex or thermosome; top center the CCT chaperonin of Group II complex typically resident of the eukaryotic-cell cytosol; and top right the chaperonin of Group I (Hsp60 or Cpn60) complex (with Hsp10 on top) characteristic of bacteria and eukaryotic-cell mitochondria. Archaeal species vary in their content of chaperonin genes–proteins from only one through a maximum (at least from what we know at the present time) of five. These subunits are variously designated with Arabic numbers, English letters, or Greek letters. As far as we know, they all form a hexadecameric megadalton sized complex, the thermosome, of the type shown on top to the left, which is an example of a hexadecamer found in archaea encoding only one chaperonin subunit, e.g., P. furiosus. The composition of hexadecamers in all archaea that have two or more subunits is not yet fully elucidated. M. thermautotrophicus, Methanothermobacter thermautotrophicus ΔH, previously known as Methanobacterium thermoautotrophicum ΔH. M. mazei, Methanosarcina mazei. (Reproduced with permission from ref. 59, published under the CC-BY license)
