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Chapter 4
The full list of all the chimeras that were attempted for this chapter have been shown below
in table 4.1. In these experiments, two different groups of chimeras were attempted. Initially,
I constructed chimeras where the apical domains and segments of the intermediate domains
were swapped. These swaps were attempted as a result of similar work done on
mitochondrial chaperonin by Nielsen and Cowan (Nielsen & Cowan, 1998). In these
chimeras the junction points of the fusions were at I144 and A405 for GroEL and I143 and
A403 for Cpn60.1 and Cpn60.2. For the purpose of this chapter, this group of chimeras will
be referred to as imprecise chimeras (due to the imprecise nature of the apical domain swap).
The complementation and expression results obtained from these chimeras can be seen in
section 4.1. After the construction of these chimeras it was noted that the inclusion of partial
segments of the intermediate domain, rather than the entire domain, was causing issues
during the chaperonin cycle. In some cases this would result in cell death, while in others the
complete loss of ability to function where they would not be expected to. To ensure that the
results of these experiments were not being influenced by the inclusion of a partial segment
of the intermediate domain, it was decided that a second group of chimeras, where only the
apical domain was precisely swapped, would be made. The junction points for the fusions of
the precise domain swaps were at E191 and V377 for GroEL and G190 and V376 for
Cpn60.1 and Cpn60.2. For the remainder of this chapter, these chimeras will be referred to as
precise chimeras (due to the precise nature of the apical domain swaps). The
complementation and expression results of these chimeras can be seen in section 4.2.
Using these chimeric proteins, attempts were made to ascertain the roles played by the apical
and equatorial domains in the functional and structural properties of chaperonins. The table
below lists all the chimeras attempted, and a simple hypothesis associated with each one.
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