Component of the EKC/KEOPS complex that is required for the formation of a threonylcarbamoyl group on adenosine at position 37 (t(6)A37) in tRNAs that read codons beginning with adenine. The complex is probably involved in the transfer of the threonylcarbamoyl moiety of threonylcarbamoyl-AMP (TC-AMP) to the N6 group of A37. BUD32 has ATPase activity in the context of the EKC/KEOPS complex and likely plays a supporting role to the catalytic subunit KAE1. The EKC/KEOPS complex also promotes both telomere uncapping and telomere elongation. The complex is required for efficient recruitment of transcriptional coactivators. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Component of the EKC/KEOPS complex composed of at least bud32, cgi121, gon7, kae1 and pcc1; the whole complex dimerizes. This protein is considered an atypical serine/threonine kinase, because it lacks the conventional structural elements necessary for the substrate recognition as well as a lysine residue that in all other serine/threonine kinases participates in the catalytic event (By similarity). BUD32 has protein kinase activity in vitro, but in the context of the EKC/KEOPS complex, the catalytic subunit KAE1 switches the activity of BUD32 from kinase into ATPase (By similarity). Belongs to the protein kinase superfamily. BUD32 family.