Ascenzi Paolo, Visca Paolo
National Institute for Infectious Diseases IRCCS Lazzaro Spallanzani, Rome, Italy.
Methods Enzymol. 2008;436:317-37. doi: 10.1016/S0076-6879(08)36018-2.
Tuberculosis and leprosy are among the most challenging infectious threats to human health. The ability of mycobacteria to persist in vivo in the presence of reactive nitrogen and oxygen species implies the presence in these bacteria of effective detoxification (pseudoenzymatic) systems. Mycobacterium tuberculosis and Mycobacterium leprae truncated hemoglobins (trHbs) belonging to group I (or N; trHbN) and group II (or O; trHbO) have recently been implicated in the scavenging of nitrogen monoxide (*NO) and peroxynitrite (ONOO-/HOONO). Furthermore, M. leprae trHbO was found to act as an efficient scavenger of the strong oxidant trioxocarbonate(1-) (CO3-) following the reaction of peroxynitrite with carbon dioxide (CO2). Here, mechanisms for scavenging of reactive nitrogen species by mycobacterial trHbs are reviewed, and detailed protocols for assessing pseudoenzymatic kinetics are provided.
结核病和麻风病是对人类健康最具挑战性的传染性威胁之一。分枝杆菌在活性氮和氧存在的情况下在体内持续存在的能力意味着这些细菌中存在有效的解毒（假酶）系统。最近，属于第一组（或N组；trHbN）和第二组（或O组；trHbO）的结核分枝杆菌和麻风分枝杆菌截短血红蛋白（trHb）与一氧化氮（*NO）和过氧亚硝酸盐（ONOO-/HOONO）的清除有关。此外，发现麻风分枝杆菌trHbO在过氧亚硝酸盐与二氧化碳（CO2）反应后可作为强氧化剂三氧碳酸盐（1-）（CO3-）的有效清除剂。本文综述了分枝杆菌trHb清除活性氮物种的机制，并提供了评估假酶动力学的详细方案。
