HPLC chromatographic traces (CHIRALPAK AD-H
column, λ = 280
nm) of β-etherase enzyme assay samples from cosubstrates racem-GβS and glutathione. Chromatographic regions
for syringaldehyde (gray), Gβ(S)S (green),
and Gβ(R)S (orange) peak elution times are
highlighted by shading. (A) No enzyme added, 0 h sample, where the
ratio of peak area integrals of Gβ(S)S to Gβ(R)S was ∼1:1. After 1 h incubation with either enzymatic
catalyst: (B) NaLigE, (C) NsLigE, (D) SsLigE, (E) SsLigP, (F) NaLigF1,
(G) NaLigF2, or (H) SsLigF1. Structures of syringaldehyde, Gβ(S)S, and Gβ(R)S are shown in Figure 1B. Abbreviations: Na, N. aromaticivorans strain DSM12444; Ns, Novosphingobium sp. strain
PP1Y; Ss, Sphingobium sp. strain SYK-6. See Experimental Section for details.