(2S)-2-[(R)-1-carboxyethylamino]pentanoate + NAD(+) + H2O <=> L-2-aminopentanoate + pyruvate + NADH + H(+)
(2s)-2-[(r)-1-carboxyethylamino]pentanoate + nad(+) + h2o <=> l-2-aminopentanoate + pyruvate + nadh + h(+)