New donors—new products: Threonine aldolases (L‐TA, D‐TA) have now been found to accept donors other than glycine. In a simple asymmetric biocatalytic aldol reaction alanine, serine, and cysteine reacted with a range of simple acceptor aldehydes to yielded α‐substituted serine derivatives (see scheme; PLP=pyridoxal phosphate).