Harpinpss是一種病源蛋白，是由Pswudomonas syringae pv. syringae hrp基因群的hrpZ所表現，會引發菸草 (Nicotiana tabacum L. cv. Xanthi)的過敏反應。在harpin處理六小時後就可以看到組織損傷，並且在12小時後更為明顯。在處理後24小時木質素含量約為對造組的2.5倍。
用等電點焦集電泳法可發現在harpin處理的菸草組織中有六種過氧化酵素的同功酵素(pI 9.5, pI 8.7, pI 5.3, pI 4.4, pI 3.7, and pI 3.5)及七種laccase的同功酵素 (pI 9.4, pI 8.6, pI 7.8, pI 5.4, pI 4.5, pI 3.8, and pI 3.6)，其中過氧化同功酵素(pI 4.4, pI 5.3 and pI 8.7)及laccase的同功酵素(pI 7.8) 僅在hapin處理的組織中發現。用RT-PCR可以證明過氧化同功酵素(pI 4.4, pI 8.7, pI 9.5)活性的提升，與transcript的增加有關。

Harpinpss, a pathogenic protein, encoded by hrpZ in the hrp gene cluster from Pswudomonas syringae pv. syringae, can induce the hypersensitive response in tobacco (Nicotiana tabacum L. cv. Xanthi). The lesion area on the tobacco leaves was visible 6 h after inoculation with harpin, and was evident 12 h after inoculation. The lignin content in harpin-treated tobacco leaves was about 2.5-fold as compared with the controls 24 h after inoculation.
There were six isozymes of POD (pI 9.5, pI 8.7, pI 5.3, pI 4.4, pI 3.7, and pI 3.5) and seven isozymes of laccase (pI 9.4, pI 8.6, pI 7.8, pI 5.4, pI 4.5, pI 3.8, and pI 3.6) identified by isoelectric point in extracts of harpin-inoculated tobacco leaves. POD isozymes (pI 4.4, pI 5.3 and pI 8.7) and laccase isozyme (pI 7.8) only appeared in harpin-inoculated tissues. The increased POD isozymes (pI 4.4, pI 8.7, pI 9.5) are correlated with the rise of transcripts of these enzymes confirmed by the method of reverse transcriptase-polymerase chain reaction (RT-PCR).

Acknwledgments-------------------------------------------------------I
Chinese abstract--------------------------------------------------------II
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