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 IMs, Pv,Vs,NtNodRm-V(C16:2, S)III241, 258
Ms,VsNodRm-V(C16:2)IV, III258
Ms,Pv, Vs,NtNodRm-IV(C16:2, S)None241, 258
Ms, Pv, Vs,NtNodRm-IV(C16:2)III241, 258
VuNodNGR-V(AcMeFuc)Unknown structures259
VuNodNGR-V(SMeFuc)Unknown structures259
Ps, Pv,VuNodNGR-V(MeFuc)Unknown structures259
NtNodRm-IV(Ac, C16:2)None241
NtNodRlv-V(Ac, C18:4)AcIV, AcIIIOvtsyna et al., submitted
NtNodRlv-V(Ac, C18:4, Fuc)AcIIIOvtsyna et al., submitted
NtNodRlv-IV(Ac, C18:4)NoneOvtsyna et al., submitted
NtNodRlv-IV(Ac, C18:4, Fuc)NoneOvtsyna et al., submitted
Chitinase class IINtNodRm-V(C16:2, S)III241
NtNodRm-IV(C16:2, S)None241
Chitinase class IIICa, Bv,NtNodRm-V(C16:2, S)III, II241
Ca, Bv,NtNodRm-IV(C16:2, S)II241
Ca, Bv,NtNodRm-IV(C16:2)III, II241
SrNodAc factorsUnknown structures103
NtNodRm-IV(Ac, C16:2, S)None241
NtNodRm-V(Ac, C16:2, S)AcIII241
NtNodRlv-V(Ac, C18:4)AcIV, AcIIIOvtsyna et al., submitted
NtNodRlv-V(Ac, C18:4, Fuc)AcIIIOvtsyna et al., submitted
NtNodRlv-IV(Ac, C18:4)AcIIIOvtsyna et al., submitted
NtNodRlv-IV(Ac, C18:4, Fuc)NoneOvtsyna et al., submitted
Chitinase class IVBv,DcNodRm-V(C16:2, S)III241
Bv,DcNodRm-IV(C16:2, S)None241
Chitinase class VNtNodRm-V(C16:2, S)III241
NtNodRm-IV(C16:2, S)None241
Chitinase class VINtNodRm-V(C16:2, S)III241
NtNodRm-IV(C16:2, S)None241
Novel chitinase/lysozymeMsNodRm-V(C16:2, S)III179
MsNodRm-IV(C16:2, S)III179
MsNodRm-IV(Ac, C16:2, S)AcIII179
Nod factor hydrolaseMsNodRm-V(C16:2, S)II258, 260
MsNodRm-IV(C16:2, S)II258, 260
MsNodRm-IV(C16:2)II258, 260
MsNodRm-IV(Ac, C16:2, S)AcII260
MsNodRm-V(Ac, C16:2, S)AcII260
RootsMs,VsNodRm-V(C16:2, S)III, II258, 260
Ms,VsNodRm-V(C16:2)IV, III, II258
Ms,VsNodRm-IV(C16:2, S)II258, 260
Ms,VsNodRm-IV(C16:2)III, II258
MsNodRm-IV(C16:0, S)II258
Ms, Ps,VsNodRlv-V(Ac, C18:4)AcIV, AcIII, AcII97, 118
VsNodRlv-IV(Ac, C18:4)AcIII, AcII118
VsNodRlv-V(Ac, C18:0)AcIV, AcIII, AcII118
SrNodAc factorsUnknown structures103
  • 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).