FAME profiles in Pseudomonas vesicularis during catechol and phenol degradation in the presence of glucose as an additional carbon source

The aim of this study was to evaluate the impact of catechol and phenol added to culture media separately and with glucose as an additional, easily-degradable carbon source on fatty acid methyl ester (FAME) composition in Pseudomonas vesicularis. Simultaneously, the degradation rates of aromatic substrates used were investigated in single and binary substrate systems. Both catechol and phenol treatments caused changes in the distribution of tested groups of fatty acids. The most noticeable changes included an increase in degree of fatty acid saturation, the appearance of branched and disappearance of hydroxy fatty acids as compared to the control sample with glucose. Under catechol or phenol treatment sat/unsat ratio showed the values of 8.63 and 11.38, respectively, whereas in contr ol cells it reached the value of 2.66. The high level of saturation comes from the high content of cyclopropane fatty acids in bacteria under exposure to aromatic substrates, regardless of the presence of glucose. In these treatments their content was more than 3-fold higher compared to the control. It has been demonstrated that glucose supplementation of culture media containing single aromatic substrate extended the degradation rates of catechol and phenol by P. vesicularis, caused an increase in number of cells but did not significantly change the fatty acid profiles in comparison with bacteria growing on catechol and phenol added to the media individually

Isolation and characterization of a novel strain of stenotrophomonas maltophilia possessing various dioxygenases for monocyclic hydrocarbon degradation

A Gram-negative bacterium, designated as strain KB2, was isolated from activated sludge and was found to utilize different aromatic substrates as sole carbon and energy source. On the basis of morphological and physiochemical characteristics and 16S rRNA gene sequence analysis, the isolated strain KB2 was identified as Stenotrophomonas maltophilia. Strain KB2 is from among different Stenotrophomonas maltophilia strains the first one described as exhibiting the activities of three types of dioxygenases depending on the structure of the inducer. The cells grown on benzoate and catechol showed mainly catechol 1,2- dioxygenase activity. The activity of 2,3-dioxygenase was detected after phenol induction. Protocatechuate 3,4-dioxygenase was found in crude cell extracts of this strain after incubation with 4-hydroxybenzoic acid, protocatechuic acid and vanillic acid. Because of broad spectrum of dioxygenases' types that Stenotrophomonas maltophilia KB2 can exhibit, this strain appears to be very powerful and useful tool in the biotreatment of wastewaters and in soil decontamination

Whole cell-derived fatty acid profiles of Pseudomonas sp. JS150 during naphthalene degradation

Changes in cellular fatty acid composition during naphthalene degradation, at the concentrations of 0.5 g lñ1 or 1.0 g lñ1,by Pseudomonas sp. JS150 were investigated. In response to naphthalene exposure an increase in saturated/unsaturatedratio was observed. Additionally, the dynamic changes involved alterations in the contents of hydroxy, cyclopropaneand branched fatty acids. Among the classes of fatty acids tested the most noticeable changes in the abundance ofcyclopropane fatty acids were observed. Since day 4 of incubation these fatty acids were not dectected in bacterial cellsgrowing on naphthalene. In contrast, markedly increased in the percentage of hydroxy fatty acids over time wasobserved. However, the proportions of saturated straight-chain and branched fatty acids did not change such significantly

Molekularne podstawy rozkładu ksenobiotycznych związków aromatycznych

Aromatic compounds in the environment can be of natural or anthropological origins. Xenobiotic arenes are found to be weakly degraded because of the presence of stable aromatic ring (due to the delocalization of their orbitals) and different constituents which can impede biodegradation rate. That’s why the cleavage of aromatic ring by dioxygenases of bacterial origin is the critical step in removing of theses xenobiotics from environment. Also, monooxygenases play important role in biotransformation of the initial structure to one of the central intermediates: catechol, hydroquinone, protocatechuate or gentisate. In biodegradation of haloaromatics, dehalogenases are the essential enzymes in removing these xenobiotics

Enzymy uczestniczące w biodegradacji polimerów

Most widely used plastics are considered to be resistant to environmental factors. Degradation of most popular packaging polymer is slow and may take hundreds of years. To enhance their environmental degradation, a number of different approaches, among them copolymerisation or compounding with additives susceptible to environmental factors such as polyesters are used. Enzymes involved in decomposition of polyesters are mainly hydrolases i.e. esterases, lipases, cutinases. The research team in the Department of Biochemistry is working on polyethylene and poly(ethylene terephtalate) films modified with synthetic aliphatic polyester Bionolle® and mechanisms of their biodegradation using fungal extracellular hydrolytic enzymes

Transformation of "E. coli" with plasmids coding for degradation of aromatic structure of phenols

Recently much attention is paid to the ability of microorganisms to degrade and detoxify large amounts of aromatic compounds enter­ing the environment as a result of man's indus­trial and agricultural activity [1]. Different genera of bacteria are a ble to metabolize a vast majority of natura( and synthetic aromatic compounds [2). These microorganisms are ca­pa ble of inducing synthesis of catabolic enyzmes thai initiate degradation of severa( phenolic compounds[...

A comparative study of biodegradation of vinyl acetate by environmental strains

Four Gram-negative strains, E3_2001, EC1_2004, EC3_3502 and EC2_3502, previously isolated from soil samples, were subjected to comparative studies in order to select the best vinyl acetate degrader for waste gas treatment. Comparison of biochemical and physiological tests as well as the results of fatty acids analyses were comparable with the results of 16S rRNA gene sequence analyses. The isolated strains were identified as Pseudomonas putida EC3_2001, Pseudomonas putida EC1_2004, Achromobacter xylosoxidans EC3_3502 and Agrobacterium sp. EC2_3502 strains. Two additional strains, Pseudomonas fluorescens PCM 2123 and Stenotrophomonas malthophilia KB2, were used as controls. All described strains were able to use vinyl acetate as the only source of carbon and energy under aerobic as well as oxygen deficiency conditions. Esterase, alcohol dehydrogenase and aldehyde dehydrogenase were involved in vinyl acetate decomposition under aerobic conditions. Shorter degradation times of vinyl acetate were associated with accumulation of acetic acid, acetaldehyde and ethanol as intermediates in the culture fluids of EC3_2001 and KB2 strains. Complete aerobic degradation of vinyl acetate combined with a low increase in biomass was observed for EC3_2001 and EC1_2004 strains. In conclusion, P. putida EC1_2004 is proposed as the best vinyl acetate degrader for future waste gas treatment in trickle-bed bioreactors

Zróżnicowanie mieszanych populacji mikroorganizmów po skriningu w obecności wybranych lotnych związków organicznych

Biological methods of productive gases treatment from Volatile Organic Compounds are based on the catalytic activities of degradative enzymes from environmental microorganisms. That is why screening for microorganisms able to degrade xenobiotics is performed. In order to isolate microorganisms able do degrade selected VOCs (vinyl acetate and styrene), soil sampling was performed in the area of Synthos S.A. in Oswiecim (Poland) (formerly Chemical Company “Dwory” S.A.) in August 2006. Two independent localizations were chosen for the collection of samples, and they were the outlet of gases arising during polymerisation of polyvinyl acetate and polystyrene. Different selection media were applied. They consisted of mineral salts solution, buffer components, and selective factor. As the selective factor increasing concentrations (50÷4000 mg/dm3) of vinyl acetate or constant concentration of styrene (100 mg/dm3) were applied. There was no increase of styrene concentration due to the significant drop in the amount of mixed population of microorganisms after application of that selective factor. Isolation, determination of microorganisms’ amount on the grounds of colony morphology and results of the Gram staining of cells, were carried out after introduction of vinyl acetate in the concentrations of 1500, 2000, 2500, 3000 and 3500 mg/dm3, and at the end of 6 weeks adaptation to styrene. Presence of selected VOCs caused significant changes in the amount and composition of mixed population of microorganisms. Both, vinyl acetate and styrene, resulted in the decrease of the initial number of populations. The ratio of Gram-negative to Gram-positive cells was changing in the presence of selected VOCs. In the beginning Gram-negative bacteria predominated. Increasing concentrations of vinyl acetate brought about gradual decrease in the number of Grampositive bacteria, and finally after application of 3000 mg/dm3 of vinyl acetate mixed populations consisted of only Gram-negative bacteria. Different chemical structure of styrene probably caused almost complete decay of Gramnegative bacteria in the presence of that selective factor. Differences in the structure of the bacterial cell envelopes are most likely the reason of increased survivability of Gram-positive bacteria, mainly filiform cells of Actinomycetes