Financial support for this project was provided by the Washington
State Department of Transportation (Grant No. T1462-03). The WSU
NMR Center equipment was supported by NIH grants RR0631401 and
RR12948, NSF grants CHE-9115282 and DBI-9604689 and the Murdock
Charitable Trust. We thank Patrick Freeze for NMR and FTIR experiments,
and Jenifer McIntyre for discussions on copper toxicity. Funding
was further provided by the Washington State University Agricultural
Research Center through Projects 0152 and 0267.