... already containing two copies of each of the bc1subunits plus the monomeric form of Bcs1p) and (b) the 500 kDa bc1sub-complex containsa single copy of each of the bc1subunits which, in ... oligomeric forms of bc1assembly factors [12,29,32,41]. Of course, thepossibility that other protein components of the respi-ratory chain, such as subunits of the cytochrome coxidase, or of the TIM23 ... assembly of the bc1complex is alsounknown. Furthermore, as in the case of the biogene-sis of other multi-subunit complexes of the mitochon-drial respiratory chain, the assistance of specificchaperone...