Table 2. Conserved catalytic residues of different Alr enzymes and their equivalent positions.

Alr source	Catalytic residues
O. oeni	Lys39	Tyr266
E. faecalis	Lys40	Tyr267
B. stearothermophilus	Lys39	Tyr265
B. anthracis	Lys41	Tyr274
S. aureus	Lys39	Tyr269
S. pneumoniae	Lys40	Tyr267