title: Modifications of the cell wall of yeasts grown on hexadecane and under starvation conditions.
abstract: Electron-microscopic examinations have demonstrated local modifications in the cell wall of the yeast Candida maltosa grown on hexadecane. In our earlier studies, these modified sites, observed in other yeasts grown on oil hydrocarbons, were conventionally called 'canals'. The biochemical and cytochemical studies of C. maltosa have revealed a correlation between the formation of 'canals' and decrease in the amount of cell wall polysaccharides, glucan and mannan. The ultrathin sections and surface replicas have shown that the 'canals' are destroyed by pronase, thus indicating that a significant proportion of their content is represented by proteins. This finding was compatible with our earlier data on the localization of oxidative enzymes in 'canals' and possible participation of the 'canals' in the primary oxidation of hydrocarbons. A completely unexpected and intriguing phenomenon has been the appearance of 'canals' in the yeast C. maltosa under starvation conditions. Unlike the yeasts grown on hexadecane, mannan almost disappears in starving cells, while the quantity of glucan first decreases and then is restored to its initial level. The role of 'canals' in starving cells is as yet unclear; it is assumed that they acquire exoenzymes involved in the utilization of products of cell lysis in the starving population. In the future, 'canals' of starving cells will be studied in connection with their possible participation in apoptosis.
authors.affiliation: G. K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Russian Federation.
authors.forename: Vladimir V
authors.initials: VV
authors.lastname: Dmitriev
authors.affiliation: Department of Environmental Sciences, University of California, Riverside, CA, USA.
authors.forename: David E
authors.initials: DE
authors.lastname: Crowley
authors.affiliation: G. K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Russian Federation.
authors.forename: Anton N
authors.initials: AN
authors.lastname: Zvonarev
authors.affiliation: G. K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Russian Federation.
authors.forename: Tatiana G
authors.initials: TG
authors.lastname: Rusakova
authors.affiliation: Argonne National Laboratory, Lemont, IL, USA.
authors.forename: Maria C
authors.initials: MC
authors.lastname: Negri
authors.affiliation: G. K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Russian Federation.
authors.forename: Svetlana A
authors.initials: SA
authors.lastname: Kolesnikova
mesh_terms: D000473:Alkanes / Q000378:metabolism*; D002175:Candida / Q000254:growth & development* / Q000378:metabolism / Q000648:ultrastructure; D002473:Cell Wall / Q000737:chemistry / Q000648:ultrastructure*; D003470:Culture Media; D006867:Hydrolases / Q000378:metabolism; D008351:Mannans / Q000378:metabolism; D008854:Microscopy, Electron
chemical_list: D000473:Alkanes; D003470:Culture Media; D008351:Mannans; D006867:Hydrolases; C040676:gluculase; C007932:n-hexadecane
keywords: 'canals'; cell wall; polysaccharides; starvation; yeast