We use cookies to ensure that we give you the best experience on our website Learn more

May 15, 2018

Congress of the International Society for Human and Animal Mycology

4 / Comparative study of lipid composition of the mycelial cell wall from environmental and clinical isolates of Histoplasma capsulatum

;

Luisa F. Gómez;

Carlos A. Peláez;

María del P. Jiménez

histoplasma capsulatum

environmental isolates

clinical isolates

lipid

mycelial cell wall

Abstract

Abstract

thumbnail

Keywords

histoplasma capsulatum

environmental isolates

clinical isolates

lipid

mycelial cell wall

Abstract

Compare the lipid composition of the mycelial cell wall from environmental and clinical isolates of Histoplasma capsulatum Histoplasma capsulatum isolates Clinical isolates 1402065 was obtained by means of a biopsy of a patient that was analyzed in the Grupo de Micología Médica and environmental isolates 316-1 was obtained by samples of organic amendments in the Grupo Interdisciplinario de Estudios Moleculares of the Universidad de Antioquia. These isolates remained in mycelial phase in the Mycosel environment at 23°C Lipid extraction The strains used in this study was store in hexane solvent for 6 months at 23°C and monitored monthly to guarantee inactivity of the extract. The lyophilized cultures were subjected to Soxhlet extraction whit four solvents consecutively, hexane, chloroform isopropanol and methanol. Derivatization and preparation of FAMEs The different extracts were treated with sodium hydroxide in methanol at 90 °C under a reflux system for 7 min. Thereafter, 5 ml of 20% boron trifluoride in methanol was added and maintained under a reflux system. Then the samples were mixed with 4 mL of n-heptane and allowed to reflux for one additional min. The organic phases were then collected into Eppendorf tubes with anhydrous sodium sulfate to dry the samples and centrifuged at 13.000 rpm for 7 min. Gas chromatography Two microliters of a solution containing the internal standards mixture of FAMEs, followed by the different extracts that were run independently in the Agilent 6890N gas chromatograph with flame ionization detector. Composition of fatty acids In all extract five fatty acids could be detected. Myristic, palmitic, stearic, oleic, and linoleic acids, except in the hexane extract the linolenic acid could be detected. In the hexane extract the most abundant fatty acids were palmitic, oleic and linoleic acids, with an unsaturation index of 2.2 (environmental) and 2.1 (clinical). In the chloroform extract the most abundant fatty acids were palmitic, stearic, oleic and linoleic acids, with an unsaturation index of 1.8 (environmental) and 1.3 (clinical). In isopropanol extract of the environment isolate the most abundant fatty acids were palmitic, stearic, oleic and linoleic acids, with an unsaturation index of 1.6. unlike clinical isolation, the most abundant fatty acids were palmitic, oleic and linoleic acids with an unsaturation index of 2.6. In the methanol extract the most abundant fatty acids were myristic, palmitic, stearic and oleic acids, with an unsaturation index of 0.6 (environmental) and 0.7 (clinical). The proportion of unsaturated fatty acids in the environment decreases continuously as the polarity of the solvent increases, except in the clinical isolates, where there is a large decrease in stearic acid in the extract with isopropanol, presenting significant differences in the index of unsaturation 2.6. These differences indicate that H. capsulatum primary isolation changes its relationship between the saturated and unsaturated fatty acids of the cellular cell to be able to adapt to the body temperature of the host. The lipid difference between the isolates contribute significantly for understanding of lipid metabolism in pathogenic fungi can help the development of more efficient antifungal therapeutic strategies.

Discover over 20,000 new abstracts, posters and presentations from leading academic conferences every month. Stay on top of the latest findings, methodologies and discussions happening in your research field around the world.

Company

Legal

Follow us

© Copyright 2019 Morressier GmbH. All rights reserved.

© Copyright 2019 Morressier GmbH.
All rights reserved.