López-Solanilla E, García-Olmedo F, Rodríguez-Palenzuela P
Departamento de Biotecnología, Universidad Politécnica de Madrid, E.T.S. Ingenieros Agrónomos, Ciudad Universitaria s/n, E-28040 Madrid, Spain.
Plant Cell. 1998 Jun;10(6):917-24.
We investigated the role in pathogenesis of bacterial resistance to plant antimicrobial peptides. The sapA to sapF (for sensitive to antimicrobial peptides) operon from the pathogenic bacterium Erwinia chrysanthemi has been characterized. It has five open reading frames that are closely related (71% overall amino acid identity) and are in the same order as those of the sapA to sapF operon from Salmonella typhimurium. An E. chrysanthemi sap mutant strain was constructed by marker exchange. This mutant was more sensitive than was the wild type to wheat alpha-thionin and to snakin-1, which is the most abundant antimicrobial peptide from potato tubers. This mutant was also less virulent than was the wild-type strain in potato tubers: lesion area was 37% that of the control, and growth rate was two orders of magnitude lower. These results indicate that the interaction of antimicrobial peptides from the host with the sapA to sapF operon from the pathogen plays a similar role in animal and in plant bacterial pathogenesis.
我们研究了细菌对植物抗菌肽耐药性在发病机制中的作用。已对致病细菌菊欧文氏菌中对抗菌肽敏感的sapA至sapF操纵子进行了表征。它有五个开放阅读框，彼此密切相关（总体氨基酸同一性为71%），且与鼠伤寒沙门氏菌的sapA至sapF操纵子中的开放阅读框顺序相同。通过标记交换构建了菊欧文氏菌sap突变株。该突变株比野生型对小麦α-硫堇和蛇形抗菌肽-1（马铃薯块茎中最丰富的抗菌肽）更敏感。该突变株在马铃薯块茎中的毒性也低于野生型菌株：病斑面积为对照的37%，生长速率低两个数量级。这些结果表明，宿主的抗菌肽与病原体的sapA至sapF操纵子之间的相互作用在动物和植物细菌发病机制中发挥着相似的作用。
