3/2007Bacterial heavy metals resistance mechanisms – part I

AGNIESZKA JAMA-KMIECIK (Zakład Nauk Podstawowych Wydziału Zdrowia Publicznego Akademii Medycznej we Wrocławiu; Kierownik: prof. dr hab. med. Irena Choroszy-Król)

Summary
In this paper the mechanisms of bacterial resistance to heavy metals which play an important role in the life processes, such as Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni are presented. Metals such as Mg, Zn stabilize various enzymes and DNA through electrostatic forces. Fe, Mg, Ni, Co are part of complex molecules with a wide array of functions; K, Na are required for regulation of intracellular osmotic pressure. Metal resistance in microorganisms based on the six resistance mechanisms: exclusion by permeability barrier, intra- and extra-cellular sequestration, active transport efflux pumps, enzymatic detoxification, reduction in the sensitivity of the cellular targets to metal ions, is presented in detail.

Key words: resistance, heavy metals, enzymatic detoxification