Table 6.

Hydrolysis of Nod factors by chitinases and related enzymesa

EnzymePlant isozymesbNod factors used as substratesb,cAcylated products in hydrolysateb,dReference(s)
Chitinase class I Ms, Pv,Vs, Nt NodRm-V(C16:2, S) III 241,258
Ms,Vs NodRm-V(C16:2) IV, III 258
Ms,Pv, Vs, Nt NodRm-IV(C16:2, S) None 241,258
Ms, Pv, Vs, Nt NodRm-IV(C16:2) III 241,258
Vu NodNGR-V(AcMeFuc) Unknown structures 259
Vu NodNGR-V(SMeFuc) Unknown structures 259
Ps, Pv,Vu NodNGR-V(MeFuc) Unknown structures 259
Nt NodRm-IV(Ac, C16:2)None 241
Nt NodRlv-V(Ac, C18:4)AcIV, AcIIIOvtsyna et al., submitted
Nt NodRlv-V(Ac, C18:4, Fuc)AcIIIOvtsyna et al., submitted
Nt NodRlv-IV(Ac, C18:4)NoneOvtsyna et al., submitted
Nt NodRlv-IV(Ac, C18:4, Fuc)NoneOvtsyna et al., submitted
Chitinase class II Nt NodRm-V(C16:2, S)III 241
Nt NodRm-IV(C16:2, S)None 241
Nt NodRm-IV(C16:2)III 241
Chitinase class III Ca, Bv,Nt NodRm-V(C16:2, S) III, II 241
Ca, Bv,Nt NodRm-IV(C16:2, S) II 241
Ca, Bv,Nt NodRm-IV(C16:2) III, II 241
Sr NodAc factors Unknown structures 103
Nt NodRm-IV(Ac, C16:2, S)None 241
Nt NodRm-V(Ac, C16:2, S)AcIII 241
Nt NodRlv-V(Ac, C18:4)AcIV, AcIIIOvtsyna et al., submitted
Nt NodRlv-V(Ac, C18:4, Fuc)AcIIIOvtsyna et al., submitted
Nt NodRlv-IV(Ac, C18:4)AcIIIOvtsyna et al., submitted
Nt NodRlv-IV(Ac, C18:4, Fuc)NoneOvtsyna et al., submitted
Chitinase class IV Bv,Dc NodRm-V(C16:2, S)III 241
Bv,Dc NodRm-IV(C16:2, S)None 241
Bv,Dc NodRm-IV(C16:2)III 241
Chitinase class V Nt NodRm-V(C16:2, S)III 241
Nt NodRm-IV(C16:2, S)None 241
Nt NodRm-IV(C16:2)III 241
Chitinase class VI Nt NodRm-V(C16:2, S)III 241
Nt NodRm-IV(C16:2, S)None 241
Nt NodRm-IV(C16:2)III 241
Novel chitinase/lysozyme Ms NodRm-V(C16:2, S) III 179
Ms NodRm-IV(C16:2, S) III 179
Ms NodRm-IV(C16:2) III 179
Ms NodRm-IV(Ac, C16:2, S) AcIII 179
Nod factor hydrolase Ms NodRm-V(C16:2, S) II 258,260
Ms NodRm-V(C16:2) II 258
Ms NodRm-IV(C16:2, S) II 258,260
Ms NodRm-IV(C16:2) II 258,260
Ms NodRm-IV(Ac, C16:2, S) AcII 260
Ms NodRm-V(Ac, C16:2, S) AcII 260
Roots Ms,Vs NodRm-V(C16:2, S) III, II 258,260
Ms,Vs NodRm-V(C16:2) IV, III, II 258
Ms,Vs NodRm-IV(C16:2, S) II 258,260
Ms,Vs NodRm-IV(C16:2) III, II 258
Ms NodRm-IV(C16:0, S) II 258
Ms, Ps,Vs NodRlv-V(Ac, C18:4) AcIV, AcIII, AcII 97,118
Vs NodRlv-IV(Ac, C18:4) AcIII, AcII 118
Vs NodRlv-V(Ac, C18:0) AcIV, AcIII, AcII 118
Sr NodAc factors Unknown structures 103
  • a Purified enzymes (as well as whole roots) of both legumes (bold) and nonlegumes were incubated with Nod factors, and the reaction products were examined for the presence of acylated chitin fragments.

  • b Abbreviations are as follows. Hydrolases were isolated from the following legumes: Cicer arietinum(Ca), Medicago sativa (Ms),Phaseolus vulgaris (Pv), Pisum sativum(Ps), Sesbania rostrata (Sr),Vicia sativa (Vs), and Vigna unguiculata (Vu) and the nonlegumes Beta vulgaris (Bv), Daucus carota(Dc), and Nicotiana tabacum (Nt). Chemical groups are abbreviated as follows: acetyl (Ac), fucosyl (Fuc), methyl (Me), sulfate (S), methylfucose (MeFuc), acetylated methylfucose (AcMeFuc), sulfated methylfucose (SMeFuc).

  • c Nod factors were purified from A. caulinodans (NodAc), R. leguminosarum bv. viciae (NodRlv), Rhizobium sp. strain NGR234 (NodNGR), and R. meliloti (NodRm). Details of their structure, such as the presence of certain baroque decorations (for abbreviations, see footnote b), the length of the acyl chain, and the number of double bonds, are shown in brackets. Tetramers and pentamers of N-acetylglucosamine are marked as IV and V, respectively. The nonsulfated NodRm factors and fucosylated NodRlv factors are derivatives of the wild type obtained by desulfation and fucosylation with NodZ, respectively. NodRm-IV(C16:0, S) was prepared from NodRm-IV(C16:2, S) by catalytic reduction.

  • d Acylated products were separated from the substrate by reverse-phase high-pressure liquid chromatography (179, 241, 258, 260; A. O. Ovtsyna, M. Schultze, I. A. Tikhonovich, H. P. Spaink, É. Kondorosi, Á. Kondorosi, and C. Staehelin, submitted for publication) and thin-layer chromatography (97, 103, 118,258). Abbreviations: lipotetrasaccharide (IV); lipotrisaccharide (III); lipodisaccharide (II); O-acetylated lipotetrasaccharide (AcIV); O-acetylated lipotrisaccharide (AcIII); O-acetylated lipodisaccharide (AcII); Nod factors resistant to hydrolysis by the given enzyme (None).