Metabolism of 2-Chloro-4-Nitrophenol in a Gram Negative Bacterium, Burkholderia sp. RKJ 800

A 2-Chloro-4-nitrophenol (2C4NP) degrading bacterial strain designated as RKJ 800 was isolated from a pesticide contaminated site of India by enrichment method and utilized 2C4NP as sole source of carbon and energy. The stoichiometric amounts of nitrite and chloride ions were detected during the degradation of 2C4NP. On the basis of thin layer chromatography, high performance liquid chromatography and gas chromatography-mass spectrometry, chlorohydroquinone (CHQ) and hydroquinone (HQ) were identified as major metabolites of the degradation pathway of 2C4NP. Manganese dependent HQ dioxygenase activity was observed in the crude extract of 2C4NP induced cells of the strain RKJ 800 that suggested the cleavage of the HQ to γ-hydroxymuconic semialdehyde. On the basis of the 16S rRNA gene sequencing, strain RKJ 800 was identified as a member of genus Burkholderia. Our studies clearly showed that Burkholderia sp. RKJ 800 degraded 2-chloro-4-nitrophenol via hydroquinone pathway. The pathway identified in a gram negative bacterium, Burkholderia sp. strain RKJ 800 was differed from previously reported 2C4NP degradation pathway in another gram-negative Burkholderia sp. SJ98. This is the first report of the formation of CHQ and HQ in the degradation of 2C4NP by any gram-negative bacteria. Laboratory-scale soil microcosm studies showed that strain RKJ 800 is a suitable candidate for bioremediation of 2C4NP contaminated sites

Size distribution of viable airborne microbes in a Mediterranean suburban site

Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: European Aerosol Conferenc

Relationship between viable airborne microbial and inhalable particulate matter concentrations in the ambient air

Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: 3rd Congress of European Microbiologist

Antibiotic resistance in airborne viable microorganisms

Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: 3rd Congress of European Microbiologist

Variability of airborne microbial and particulate matter concentrations in a Mediterranean suburban site

Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: International Aerosol Conferenc

Airborne microbes and heavy metal toxicity

Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: 5th European Bioremediation Conferenc

Airborne microbial concentrations and PM10 levels in air conditioned offices

Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: European Aerosol Conferenc

Bacterial community dynamics during in-situ bioremediation of petroleum waste sludge in landfarming sites

Δημοσίευση σε επιστημονικό περιοδικόSummarization: In-situ bioremediation of petroleum waste sludge in landfarming sites of Motor Oil Hellas (petroleum refinery) was studied by monitoring the changes of the petroleum composition of the waste sludge, as well as the changes in the structure of the microbial community, for a time period of 14 months. The analyses indicated an enhanced degradation of the petroleum hydrocarbons in the landfarming areas. A depletion of n-alkanes of approximately 75–100% was obtained. Marked changes of the microbial communities of the landfarms occurred concomitantly with the degradation of the petroleum hydrocarbons. The results obtained from terminal restriction fragment length polymorphism (T-RFLP) analysis of polymerase chain reaction (PCR) amplified 16S rRNA genes demonstrated that bacteria originating from the refinery waste sludge and newly selected bacteria dominated the soil bacterial community during the period of the highest degradation activity. However, the diversity of the microbial community was decreased with increased degradation of the petroleum hydrocarbons contained in the landfarms. T-RFLP fingerprints of bacteria of the genera Enterobacter and Ochrobactrum were detected in the landfarmed soil over the entire treatment period of 14 months. In contrast, the genus Alcaligenes appeared in significant numbers only within the 10 month old landfarmed soil. Genes encoding catechol 2,3-dioxygenase (subfamily I.2.A) were detected only in DNA of the untreated refinery waste sludge. However, none of the genes known to encode the enzymes alkane hydroxylase AlkB, catechol 2,3-dioxygenase (subfamily I.2.A) and naphthalene dioxygenase nahAc could be detected in DNA of the landfarmed soils.Presented on: Biodegradatio