Similar substrate recognition motifs for mammalian AMP-activated protein kinase, higher plant HMG-CoA reductase kinase-A, yeast SNF1, and mammalian calmodulin-dependent protein kinase I.

We have analysed phosphorylation of the synthetic peptide AMARAASAAALARRR, and 23 variants by mammalian, higher plant and yeast members of the SNF1 protein kinase subfamily (AMP-activated protein kinase (AMPK), HMG-CoA reductase kinase (HRK-A), and SNF1 itself), and by mammalian calmodulin-dependent protein kinase I (CaMKI). These four kinases recognize motifs which are very similar, although distinguishable. Our studies define the following recognition motifs: AMPK: phi (X beta)XXS/TXXX phi; HRK-A: phi (X,beta)XXSXXX phi; Snf1: phi XRXXSXXX phi; CaMKI: phi XRXXS/TXXX phi; where phi is a hydrophobic residue (M, V, L, I or F) and beta is a basic residue (R, K or H).