Xenobiotic Biotransformation Potential of Pseudomonas Rhodesiae KCM-R₅ and Bacillus Subtilis KCM-RG₅, Tolerant to Heavy Metals and Phenol Derivatives

ABSTRACT

Two environmental bacterial isolates KCM-R₅ and KCM-RG₅ were selected from xenobiotic-polluted environment. KCM-R₅ was identified as Pseudomonas rhodesiae and KCM-RG₅ as Bacillus subtilis. KCM-R₅ demonstrated tolerance to heavy metals and KCM-RG₅—to heavy metals and phenol derivatives. Both strains were studied for xenobiotic biotransformation in order to contribute towards bioremediation of polluted environments. Pseudomonas rhodesiae KCM-R₅ and Bacillus subtilis. KCM-RG₅ possess unusual ability to utilize ortho-nitrophenol (o-NP) and 2,4- dichlorophenoxyacetic acid (2,4-D). o-NP and 2,4-D were added at concentration 30 mg/l. The possible indictive/inhibiting effect of Pb cations (40mg/l) was also studied. Pseudomonas rhodesiae KCM-R₅ removed 86% of o-NP and below 1% of 2,4-D. Bacillus subtilis KCM-RG5 eliminated 83% of o-NP and under 1% of 2,4-D. Biotransformation effectiveness of o-NP reached 95–100% in contrast to 2,4-D where the effectiveness was just 15–20%. Cell morphological changes were registered during the biotransformation processes. The obtained results could contribute to manage bioremediation processes in polluted with heavy metals and phenol derivatives environments.