In the course of studies on degradation of dietary fiber by the human colon bacteria, a number of Bacteroides strains from the human colon have been found to degrade polygalacturonic acid and/or pectin. Four of these strains were examined for presence of polygalacturonate lyase (PGAL). The Bacteroides strains studied synthesized inducible, cell-associated PGALs when the bacteria were grown on media containing polygalacturonic acid or on peanut cell wall (a prototype dietary fiber with a uronide content of 14.0%) as the sole carbon source. No PGAL activity could be detected in cultures grown on media containing glucose or D-galacturonate. The PGALs produced by the four Bacteroides strains had properties similar to other bacterial PGALs: An alkaline pH optima (8.5), stimulation of activity by calcium ions. complete inhibition by ethylenediaminetetraacetic acid (EDTA), preference for polygalacturonic acid as a substrate over pectin, and accumulation of unsaturated products which absorb at 235 nm. The Bacteroides PGALs catalyzed partial degradation of the uronides of peanut cell wall substrate, but at a slower rate compared to their action on polygalacturonic acid substrate. / M.S.
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/102592 |
| Date | January 1983 |
| Creators | Chastain, Jane L. |
| Contributors | Food Science and Technology |
| Publisher | Virginia Polytechnic Institute and State University |
| Source Sets | Virginia Tech Theses and Dissertation |
| Language | English |
| Detected Language | English |
| Type | Thesis, Text |
| Format | v, 60 leaves, application/pdf, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | OCLC# 10185572 |
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