Agrotechnological Research Institute (ATO-DLO), Haagsteeg 6, P.O. Box 17, NL-6700 AA Wageningen, The Netherlands.
Appl Environ Microbiol. 1993 Nov;59(11):3648-53. doi: 10.1128/aem.59.11.3648-3653.1993.
The in planta induction of anaerobic nitrate respiration by Erwinia carotovora subsp. atroseptica in relation to the in situ oxygen status in soft rotting potato tubers has been investigated. In vitro experiments have shown that nitrate was required for the induction of respiratory nitrate reductase activity in E. carotovora. In addition, oxygen was found to repress this activity. Expression of respiratory nitrate reductase was found in E. carotovora cells extracted from soft rotting potato tuber tissue. However, the rate of nitrite production in these cells was approximately 70-fold lower than the rate recorded in fully induced anaerobic cultures. Oxygen measurements in soft rotting potato tubers indicated that the invading bacteria encounter the lowest oxygen concentration at the interphase between healthy and macerated tissue. Consequently, growth of bacteria present in this specific zone will be stimulated by nitrate which is present in sufficient amounts in tuber tissue. A high nitrate content of the tuber will most likely facilitate the proliferation of E. carotovora in the tuber tissue.
已研究了胡萝卜软腐欧文氏菌亚种（Erwinia carotovora subsp. atroseptica）在与现场氧气状态相关的植物体内诱导厌氧硝酸盐呼吸的情况。体外实验表明，硝酸盐是诱导胡萝卜软腐欧文氏菌呼吸硝酸盐还原酶活性所必需的。此外，氧气被发现抑制这种活性。从软腐马铃薯块茎组织中提取的胡萝卜软腐欧文氏菌细胞中发现了呼吸硝酸盐还原酶的表达。然而，这些细胞中亚硝酸盐的产生速率比完全诱导的厌氧培养物中的记录速率低约 70 倍。在软腐马铃薯块茎中的氧气测量表明，侵入细菌在健康组织和糜烂组织之间的界面处遇到最低的氧气浓度。因此，在这个特定区域存在的细菌的生长将受到在块茎组织中存在的足够量的硝酸盐的刺激。块茎中高含量的硝酸盐很可能有助于胡萝卜软腐欧文氏菌在块茎组织中的增殖。
