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Updated: Aug 25, 2026
09:27
Functional Complementation Analysis (FCA): A Laboratory Exercise Designed and Implemented to Supplement the Teaching of Biochemical Pathways
Published on: June 24, 2016
L-alanine auxotrophy of Lactobacillus johnsonii as demonstrated by physiological, genomic, and gene complementation
Hengameh van der Kaaij1, Frank Desiere, Beat Mollet
1Nestlé Research Centre, Nestec, Ltd., CH-1000 Lausanne 26, Switzerland.
Applied and Environmental Microbiology
|March 10, 2004
Abstract:
Using a chemically defined medium without L-alanine, Lactobacillus johnsonii was demonstrated to be strictly auxotrophic for that amino acid. A comparative genetic analysis showed that all known genes involved in L-alanine biosynthesis are absent from the genome of L. johnsonii. This auxotrophy was complemented by heterologous expression of the Bacillus subtilis L-alanine dehydrogenase.
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