Question about signal cleavage site of SDHA flavoprotein:

N-term sequencing of bovine FP gave 1-SAKVSDA. Numbering like this, the flavin-binding histidine is H56 : Birch-Machin, M. A., Farnsworth, L., Ackrell, B. A., Cochran, B., Jackson, S., Bindoff, L. A., Aitken, A., Diamond, A. G. & Turnbull, D. M. (1992). The sequence of the flavoprotein subunit of bovine heart succinate dehydrogenase. J Biol Chem 267, 11553-8. However for the porcine FP the N-term sequence is SSAKV. This makes the Flavin-ligand H57, and all other numbers advanced 1 also: Huo, X., Su, D., Wang, A., Zhai, Y., Xu, J., Li, X., Bartlam, M., Sun, F. & Rao, Z. (2007). Preliminary molecular characterization and crystallization of mitochondrial respiratory complex II from porcine heart. Febs J 274, 1524-9. (The latter cutting point was confirmed for human FP by mass spec, but I don't remember the reference.)