ISSN:
1432-0991
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract About 1500 hybrid broad-host-range plasmids from a genomic library ofPseudomonas saccharophila were individually transferred by conjugation fromEscherichia coli toAlcaligenes eutrophus. Direct selection for pentose-utilizing transconjugants yielded three clones capable of growth on xylose. Growth ofP. saccharophila as well as the transconjugants ofA. eutrophus on xylose was relatively slow, exhibiting doubling times of about 9.5 h. Plasmid pGN3 harbored by one transconjugant contained a 28-kb DNA insert, 16.4 kb of which comprised the minimal information required for xylose utilization byA. eutrophus. At least thexyl genes encoding xylose isomerase and xylulokinase were located within this region, as indicated by their induction during growth ofA. eutrophus (pGN3) on xylose. Southern hybridizations with a heterologous gene probe confirmed the presence of thesexyl genes. In bothP. saccharophila andA. eutrophus (pGN3), low activities of several enzymes operating in the pentose phosphate and Entner-Doudoroff pathways might limit the rate of xylose catabolism.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01570757
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