Microorganisms form exocellular structures, trophosomes, to facilitate biodegradation of oil in aqueous media.

Autor: Dmitriev VV; G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Russia. vdmitrieva@ibpm.pushchino.ru, Crowley D, Rogachevsky VV, Negri CM, Rusakova TG, Kolesnikova SA, Akhmetov LI
Jazyk: angličtina
Zdroj: FEMS microbiology letters [FEMS Microbiol Lett] 2011 Feb; Vol. 315 (2), pp. 134-40. Date of Electronic Publication: 2010 Dec 23.
DOI: 10.1111/j.1574-6968.2010.02184.x
Abstrakt: Cytochemical staining and microscopy were used to study the trophic structures and cellular morphotypes that are produced during the colonization of oil-water interfaces by oil-degrading yeasts and bacteria. Among the microorganisms studied here, the yeasts (Schwanniomyces occidentalis, Torulopsis candida, Candida tropicalis, Candida lipolytica, Candida maltosa, Candida paralipolytica) and two representative bacteria (Rhodococcus sp. and Pseudomonas putida) produced exocellular structures composed of biopolymers during growth on petroleum hydrocarbons. Four of the yeasts including S. occidentalis, T. candida, C. tropicalis and C. maltosa excreted polymers through modified sites in their cell wall ('canals'), whereas C. lipolytica and C. paralipolytica and the two bacterial species secreted polymers over the entire cell surface. These polymers took the form of fibrils and films that clogged pores and cavities on the surfaces of the oil droplets. A three-dimensional reconstruction of the cavities using serial thin sections showed that the exopolymer films isolated the ambient aqueous medium together with microbial cells and oil to form both closed and open granules that contained pools of oxidative enzymes utilized for the degradation of the oil hydrocarbons. The formation of such granules, or 'trophosomes,' appears to be a fundamental process that facilitates the efficient degradation of oil in aqueous media.
(© 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.)
Databáze: MEDLINE