TABLE 1.

Molecular properties of strains with mutations or deletions that result in the loss of covalent flavinylation in Sdh1

The double C630A,R638A and the single R582W mutations at or near the C terminus lead to loss of SDH assembly as well as binding to heme-agarose beads. However, mutations or deletions that maintain heme-agarose binding also maintain SDH assembly. ND, not determined.

Strain	Heme binding	SDH assembly	Sdh2 steady-state	Sdh5 steady-state	Sdh1-Sdh5 interaction
H90S	Yes	Yes	Down	Stable	Attenuated
sdh5Δ	Yes	Yes	Down
ClipK	No	No	Absent	ND	ND
C630A,R638A	No	No	Absent	Unstable	Attenuated
R582A	No	No	Absent	Unstable	Attenuated