Crude oil degradation efficiency of a recombinantAcinetobacter baumanniistrain and its survival in crude oil-contaminated soil microcosm

Abstract

A hydrocarbon degrading Acinetobacter baumannii S30 strain, isolated from crude oil-contaminated soil, was inserted with the lux gene from the luciferase gene cassette luxCDABE. Soil microcosms were designed to study the degradation efficacy for total petroleum hydrocarbon (TPH) of crude oil by lux-tagged A. baumannii S30 pJES. Bioaugmentation of a TPH-contaminated microcosm with A baumannii S30 pJES showed that TPH levels were reduced from 89.3 to 53.9 g/kg soil in 90 days. Biodegradation of TPH by A baumannii S30 pJES was also monitored in shake flask conditions, which showed a reduction of initial TPH levels by over 50% at the end of 120 h. A lux-PCR-based approach along with the standard dilution plating with selective antibiotics was successfully utilized to monitor the survivability of the lux-tagged strain A. baumannii S30 pJES in soil microcosms and stability of the lux insert in the host strain A. baumannii S30. The selective plating technique indicated the population of A. baumannii S30 pJES to be 6.5+/-0.13 x 10(8) CFU/g at day zero (just after bioaugmentation) and 2.09+/-0.08 x 10(8) CFU/g of soil after 90 days of incubation. lux-PCR confirmed the stability of the insert in all the randomly selected colonies of A. baumannii strains from the antibiotic plates. The lux insert was stable after 50 generations in Luria Bertini broth and storage at -70 degrees C as glycerol stocks for over a year. These results revealed that the lux insert was stable and lux-tagged A. baumannii S30 strain could survive in a TPH-contaminated soil microcosm and could degrade TPH in the soil microcosm conditions. It can be used as an effective marker to monitor the survival of augmented strains at a bioremediation site.

Estudos de biodegradação de óleo diesel por consórcio microbiano coletado em Porto Velho - RO, amazônia

“…O gênero Acinetobacter é amplamente citado na literatura como potencial assimilador de hidrocarbonetos derivados de petróleo. 27 Resultados obtidos por Mishra et al 28 e por Morais e Tauk-Tornisielo 29 apontam, também, a eficiência da Acinetobacter baumannii como micro-organismo com grande potencial para biodegradação de hidrocarbonetos derivados de petróleo. Maeng et al 30 relataram que a enzima dioxigenase isolada de Acinetobacter sp foi capaz de oxidar alcanos de 10 a 30 átomos de carbono, alcenos (C 12 a C 20 ) e alguns compostos aromáticos alquilados, mas não alcanos ramificados como os isoprenoides.…”

Effects of crude oil contamination on soil physical and chemical properties in Momoge wetland of China

“…In the field, soil temperature was measured by inserting a thermometer about 5 cm deep into the soil. After removing the back-filled clean soil covering on the surface, we collected soil samples at 5 cm below the surface, and analyzed various properties in the laboratory within 24 h. The collected samples were analyzed for soil moisture by the oven drying method (Wilke, 2005), soil TPH content by a gravimetric method (Mishra et al, 2004), pH with a pH meter (Delta 326, Shanghai) (Wilke, 2005), AP as sodium bicarbonate (NaHCO 3 )extractable phosphorus (Schoenau and O′Halloran, 2008), and TOC by the potassium dichromate dilution heat colorimetric method (Bao, 1999).…”

Isolation and Characterization of 2,4-D Butyl Ester Degrading Acinetobacter sp. ZX02 from a Chinese Ginger Cultivated Soil

“…A . baumannii strains have been reported to degrade various chemicals, such as petroleum hydrocarbon of crude oil, waste car engine oil, phenol, 4-chloroaniline, and diclofop-methyl …”