Herlache T C, Hotchkiss A T, Burr T J, Collmer A
Department of Plant Pathology, Cornell University, Ithaca, New York 14853, USA.
Appl Environ Microbiol. 1997 Jan;63(1):338-46. doi: 10.1128/aem.63.1.338-346.1997.
DNA sequencing of the Agrobacterium vitis pehA gene revealed a predicted protein with an M(r) of 58,000 and significant similarity to the polygalacturonases of two other plant pathogens, Erwinia carotovora and Ralstonia (= Pseudomonas or Burkholderia) solanacearum. Sequencing of the N terminus of the PehA protein demonstrated cleavage of a 34-amino-acid signal peptide from pre-PehA. Mature PehA accumulated primarily in the periplasm of A. vitis and pehA+ Escherichia coli cells during exponential growth. A. vitis PehA released dimers, trimers, and monomers from polygalacturonic acid and caused less electrolyte leakage from potato tuber tissue than did the E. carotovora and R. solanacearum polygalacturonases.
葡萄土壤杆菌pehA基因的DNA测序显示，预测的蛋白质分子量为58,000，与另外两种植物病原体——胡萝卜软腐欧文氏菌和青枯雷尔氏菌（=假单胞菌属或伯克霍尔德菌属）的多聚半乳糖醛酸酶具有显著相似性。PehA蛋白N端的测序表明，前体PehA的34个氨基酸信号肽被切割。在指数生长期，成熟的PehA主要积累在葡萄土壤杆菌和pehA+大肠杆菌细胞的周质中。与胡萝卜软腐欧文氏菌和青枯雷尔氏菌的多聚半乳糖醛酸酶相比，葡萄土壤杆菌PehA从聚半乳糖醛酸中释放出二聚体、三聚体和单体，并且导致马铃薯块茎组织的电解质渗漏较少。
