Table 3. Yields for preparative scale reaction with 18a and pQR2189 and pQR2208 ^{a , b} .

	Conc. 18a (mM)	Equivalents IPA 27	HPLC yield 18b (200 μL) c	HPLC yield 18b (50 mL) c	Isolated yield 18b (50 mL) c	ee (%) (S)
pQR2189 a	20	10	69%	65%	64%	>99%
pQR2208 a	20	10	67%	34%	31%	>99%
pQR2189 b	50	2	55%	57%	57%	>99%
pQR2189 d	50	2	100%	86%	82%	nd e

^aReaction conditions for 20 mM scale: Amine donor 27 (200 mM), amino acceptor (20 mM), PLP (1 mM), KPi buffer pH 10 (50 mM) and clarified cell extract (0.4 mg mL^–1), 35 °C, 250 rpm, 24 h.

^bReaction conditions for 50 mM scale: Amine donor 27 (100 mM), amino acceptor (50 mM), PLP (1 mM), KPi buffer pH 10 (50 mM) and clarified cell extract (1 mg mL^–1), 30 °C, 250 rpm, 24 h.

^cTotal reaction volume.

^dReaction conditions same as for (b) but using purified pQR2189 (130 μg mL^–1).

^eNot determined.