Evolutionary aspects of urea utilization by fungi

Authors

Dhammika H. M. L. P Navarathna, University of Nebraska - Lincoln
Steven D. Harris, University of Nebraska-LincolnFollow
David D. Roberts, Center for Cancer Research NCIFollow
Kenneth W. Nickerson, University of Nebraska - LincolnFollow

Date of this Version

2010

Document Type

Article

Citation

FEMS Yeast Res 10 (2010), pp. 209–213. DOI:10.1111/j.1567-1364.2009.00602.x

Comments

U. S. government work.

Abstract

The higher fungi exhibit a dichotomy with regard to urea utilization. The hemiascomycetes use urea amidolyase (DUR1,2), whereas all other higher fungi use the nickel-containing urease. Urea amidolyase is an energy-dependent biotincontaining enzyme. It likely arose before the Euascomycete/Hemiascomycete divergence c. 350 million years ago by insertion of an unknown gene into one copy of a duplicated methylcrotonyl CoA carboxylase (MccA). The dichotomy between urease and urea amidolyase coincides precisely with that for the Ni/Co transporter (Nic1p), which is present in the higher fungi that use urease and is absent in those that do not. We suggest that the selective advantage for urea amidolyase is that it allowed the hemiascomycetes to jettison all Ni²⁺- and Co²⁺- dependent metabolisms and thus to have two fewer transition metals whose concentrations need to be regulated. Also, the absence of MccA in the hemiascomycetes coincides with and may explain their production of fusel alcohols.