San Mateo L R, Toffer K L, Kawula T H
Department of Microbiology and Immunology, School of Medicine, University of North Carolina at Chapel Hill 27599, USA.
Gene. 1998 Jan 30;207(2):251-7. doi: 10.1016/s0378-1119(97)00642-2.
Haemophilus ducreyi is the etiologic agent of the sexually transmitted disease chancroid, an ulcerative condition implicated in increased HIV transmission. There is increasing evidence for the roles of oxidative stress proteins including superoxide dismutase enzymes in the survival and persistence of pathogenic organisms within the host. The sodA gene of Haemophilus ducreyi was isolated from a genomic plasmid library on the basis of its ability to rescue the hydrogen peroxide hypersensitivity of an Escherichia coli sodA sodB strain. The H. ducreyi SodA protein also complemented the aerobic growth defect of the E. coli sodA sodB strain in minimal medium. The deduced amino-acid sequence of the H. ducreyi sodA gene product is 74 and 70% identical to the Mn-SODs of Haemophilus influenzae and E. coli, respectively. However, unlike Mn-SODs, the H ducreyi SodA protein was inhibited by hydrogen peroxide in native gels stained for SOD activity.
杜克雷嗜血杆菌是性传播疾病软下疳的病原体，软下疳是一种溃疡性疾病，与艾滋病毒传播增加有关。越来越多的证据表明，包括超氧化物歧化酶在内的氧化应激蛋白在病原体在宿主体内的存活和持续存在中发挥作用。基于其拯救大肠杆菌sodA sodB菌株对过氧化氢超敏反应的能力，从基因组质粒文库中分离出杜克雷嗜血杆菌的sodA基因。杜克雷嗜血杆菌SodA蛋白还弥补了大肠杆菌sodA sodB菌株在基本培养基中的有氧生长缺陷。杜克雷嗜血杆菌sodA基因产物的推导氨基酸序列分别与流感嗜血杆菌和大肠杆菌的锰超氧化物歧化酶有74%和70%的同一性。然而，与锰超氧化物歧化酶不同，在以超氧化物歧化酶活性染色的天然凝胶中，杜克雷嗜血杆菌SodA蛋白受到过氧化氢的抑制。
