
Full text loading...
SUMMARY: Eleven strains of Pseudomonas were isolated by selective enrichment on 4-nitrotoluene (4NT). They all utilized 4NT, 4-nitrobenzyl alcohol (4NBA) or 4-nitrobenzoate (4NBZate) as sole sources of carbon and nitrogen. One strain, TW3, was used for more detailed studies. 4NT-grown cells of TW3 take up O2 when incubated in the presence of 4NBA, 4-nitrobenzaldehyde (4NBZ) and 4NBZate. HPLC analysis of culture supernatants showed that 4NBZ and 4NBZate were formed when 4NT-grown cells were incubated with 4NBA, whereas only 4NBZate was found when they were incubated with 4NBZ. Two dehydrogenases were detected in extracts of 4NT-grown cells. 4NBA dehydrogenase could be assayed by a dye-linked assay whereas 4NBZ dehydrogenase activity was linked to NAD+ reduction. No nitrite was detected in supernatants of 4NBZate-grown cells incubated with 4NBZate but the nitrogen appeared as ammonium. The only aromatic ring-cleavage dioxygenase that was induced during growth on the nitroaromatics was protocatechuate 3,4-dioxygenase. It is proposed that the pathway for 4NT catabolism proceeds via 4NBA, 4NBZ and 4NBZate and ultimately to protocatechuate with release of the nitro group as ammonium.
Article metrics loading...
Full text loading...
References
Data & Media loading...