ARS | Publication request: PURIFICATION AND CHARACTERIZATION OF A NOVEL UREASE FROM PECAN FOLIAGE

Submitted to: Joint Meeting of the American Society of Plant Biologists and the Canadian Society of Plant Physiologists
Publication Type: Abstract Only
Publication Acceptance Date: February 28, 2006
Publication Date: August 9, 2006
Citation: Bai, C., Shu-Xia, Y., Wood, B.W. 2006. Purification and characterization of a novel urease from pecan foliage. In: Proceedings of Plant Biology Annual Meeting. Joint Meeting of the American Society of Plant Biologists and the Canadian Society of Plant Physiologists, August 5, 2006, Boston, MA, p. 217.

Interpretive Summary: There is need to reduce nitrogen application to crops from the perspective of costs, environment, and water quality. Gaining a better understanding of urease, a key enzyme associated with nitrogen usage and cycling, is important in solving these nitrogen related issues. A novel form of urease was found that possesses characteristics that potentially add to knowledge pertaining to how to increase or preserve the ability to effectively metabolize nitrogen. This information will contribute to improved nitrogen usage in agriculture.

Technical Abstract: We recently determined urease activity in pecan [Carya illinoinensis (Wangenh.) K. Koch] foliage and identified that nickel deficiency disrupts urease activity (Bai et al, 2006). A primary function of urease includes hydrolysis of urea during nitrogen cycling. We report here the purification to homogenicity of a 66-kDa urease from pecan foliage. This urease is a monomer, and is substantially smaller than known ureases from other plant sources. This purified 66-kDa urease is capable of reaching the maximum rate of urea hydrolysis within about 3 minutes, possesses an optimal reaction temperature of 40 degrees C, and a pH optimum of 8.5. Other physiological functions of this pecan urease are discussed.