Some physiological properties of an Italian isolate of “microthrix parvicella”

Abstract

“Microthrix parvicella” strain RN1, isolated by micromanipulation from an activated sludge treatment plant in Italy, is phylogenetically identical to two other isolates from Australia. Our Italian isolate of “M. parvicella” is a slow growing (μmax ranging from 0.3 to 0.5 d⁻¹), aerobic organism that exhibits nutritional versatility, being able to utilize simple and complex compounds as carbon and nitrogen sources. In pure culture, the organism cannot grow anaerobically nor is it able to denitrify. Strain RN1 is able to grow both in aerobic and in microaerophilic conditions and this metabolic versatility could give it a metabolic advantage in the activated sludge milieu.