Isolation and characterization of arsenite oxidizing Pseudomonas lubricans and its potential use in bioremediation of wastewater

Abstract

A bacterium, Pseudomonas lubricans, isolated from heavy metal laden industrial wastewater, has been shown to tolerate multiple heavy metals suggesting its importance in bioremediation of industrial effluents. P. lubricans tolerated As(III) up to 3 mg ml-1 , Cu 2+ up to 0.7 mg ml-1 , Hg 2+ up to 0.4 mg ml-1 , Ni 2+ up to 0.4 mg ml-1 and Cr 6+ up to 0.5 mg ml-1. P. lubricans showed optimum growth at pH 7 while optimum temperature for growth was 30°C. P. lubricans could oxidize As(III) 42% (42 µg mg-1 of protein), 78% (78 µg mg-1 of protein) and 95% (95 µg mg-1 of protein) from the medium after 24, 48 and 72 h of incubation at optimal conditions, respectively. The arsenite oxidizing ability shown by P. lubricans indicates its potential application in biological treatment of wastewaters contaminated with arsenic.

Screening of plant growth-promoting traits in arsenic-resistant bacteria isolated from the rhizosphere of soybean plants from Argentinean agricultural soil

“…For example, the MICs for As 3+ of other isolates were 0.5mM for Pseudomonas sp. (Valenzuela et al 2009), 16.6mM for Pseudomonas sp ORAs5 (Pepi et al 2007), 26mM for Pseudomonas putida (Chang et al 2007) and 40mM for Pseudomonas lubricans (Rehman et al 2010). This result is in agreement with the literature, where the genus Pseudomonas is broadly represented among the arsenicresistant strains isolated from environmental samples (Pepi et al 2007), because they are ubiquitous bacteria endowed with a remarkable adaptability to diverse environments (de Vincente et al 1990).…”