Figure 6.

Inhibition of the transglucanase activities of HTG by sugar mimics and oligosaccharides.

(a) Inhibitory effect of 25 selected compounds from the EDI xenobiotics collection (Chormova et al., ²⁰¹⁵), 17 oligosaccharides and glucose (all at 0.3 mm) and starch at 0.2 mg ml⁻¹ on the three transglucanase activities of Pichia‐produced HTG (acceptor substrate: [³H]XXXGol); n = 3; controls, n = 6.

(b) Concentration‐dependent inhibition by cello‐oligosaccharides of the three transglucanase activities of Pichia‐produced EfHTG or the XET activity of EfXTH‐H (acceptor: [³H]XXXGol); n = 3; data points are shown as squares (EfHTG) and circles (EfXTH‐H); controls, n = 6.

(c) Effect of glucose on the three transglucanase activities of Pichia‐produced EfHTG and the XET activity of EfXTH‐H ; n = 3; data points are shown as squares (EfHTG) and circles (EfXTH‐H).

(d) Concentration‐dependent inhibition by cellobiose of the three transglucanase activities of Equisetum fluviatile proteins extracted from young (E. young), middle‐aged (E. middle) and old (E. old) tissues; n = 3.

(e) Inhibition of CXE activity of Pichia‐produced EfHTG (P.) by cellobiose (acceptor substrates: [³H]XXXGol or [³H]XyG); n = 3.

(f) Inhibitory effect of 10 mM cellobiose on XET, MXE and CXE action (in situ) in old Equisetum tissue (E. old) fed with [³H]XXXGol for 24 h (acceptor, [³H]XXXGol; enzyme, endogenous); n = 3; data points are shown as circles.

(g) Dot‐blot showing the inhibitory effects of cellobiose (0–10 mM) on the three transglucanase activities of Pichia‐produced EfHTG (P.) and Equisetum protein extracts from young (E. y), middle‐aged (E. m) and old (E. o) tissues (acceptor: XXXGol‐sulphorhodamine); the cellulose used as donor substrate for the CXE assays was plain paper (cellulose I) or alkali‐pre‐treated paper (cellulose II); the donor substrates for XET and MXE activities were XyG‐ and MLG‐impregnated (NaOH‐untreated) paper, respectively; cont. = no enzyme.