Biodegradation of the chemically resistant but bacterially degradable C-P bond of alkylphosphonates is a pressing problem of environmental protection biotechnology. However, the environmental factors and physiological conditions for degradation of these compounds by bacteria are still obscure. The current work shows that adaptation of Escherichia coli cells to methylphosphonate (Pn) is more intensive under cell growth at 30 degreesC and does not depend on substrate concentration. Its degradation is optimal under low partial pressure of oxygen, pH of the medium 8.0, and logarithmic phase of culture growth. The increased synthesis of proteins of C-P lyase complex degrading Pn and encoded by the genes cloned in plasmids does not increase the efficiency of Pn degradation, which indicates the presence of limiting factors of unknown nature. (C) 2003 Elsevier Ltd. All rights reserved.