Characterization of Extracellular Polymeric Substances from Acidophilic Microbial Biofilms

ECU Author/Contributor (non-ECU co-authors, if there are any, appear on document)

Jillian F. Banfield (Creator)

George D. Cody (Creator)

Anna K. Harding (Creator)

Yongqin Jiao (Creator)

Matthew Schrenk (Creator)

Michael P. Thelen (Creator)

Korin E. Wheeler (Creator)

Paul Wilmes (Creator)

Institution

East Carolina University (ECU )

Web Site: http://www.ecu.edu/lib/

Abstract: We examined the chemical composition of extracellular polymeric substances (EPS) extracted from two natural microbial pellicle biofilms growing on acid mine drainage (AMD) solutions. The EPS obtained from a mid-developmental-stage biofilm (DS1) and a mature biofilm (DS2) were qualitatively and quantitatively compared. More than twice as much EPS was derived from DS2 as from DS1 (approximately 340 and 150 mg of EPS per g [dry weight] for DS2 and DS1 respectively). Composition analyses indicated the presence of carbohydrates metals proteins and minor quantities of DNA and lipids although the relative concentrations of these components were different for the two EPS samples. EPS from DS2 contained higher concentrations of metals and carbohydrates than EPS from DS1. Fe was the most abundant metal in both samples accounting for about 73% of the total metal content followed by Al Mg and Zn. The relative concentration profile for these metals resembled that for the AMD solution in which the biofilms grew except for Si Mn and Co. Glycosyl composition analysis indicated that both EPS samples were composed primarily of galactose glucose heptose rhamnose and mannose while the relative amounts of individual sugars were substantially different in DS1 and DS2. Additionally carbohydrate linkage analysis revealed multiply linked heptose galactose glucose mannose and rhamnose with some of the glucose in a 4-linked form. These results indicate that the biochemical composition of the EPS from these acidic biofilms is dependent on maturity and is controlled by the microbial communities as well as the local geochemical environment. Originally published Applied and Environmental Microbiology Vol. 76 No. 9 May 2010

Additional Information

Publication

Other

Applied and Environmental Microbiology. 76:9(May 2010) p. 2916-2922.

Language: English

Date: 2011

Keywords

extracellular polymeric substances, acidic biofilms, microbial communities, geochemical environment

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