L-leucine auxotrophy in Bifidobacterium globosum.
The enzymes involved in the biosynthetic pathway of L-leucine were studied in plasmid-negative and plasmid-positive clones derived from the RU 809 strain of the Bifidobacterium globosum species. The growth of plasmid-positive clones in synthetic medium required L-leucine. We have shown that no detectable activity of the beta-isopropylmalate dehydrogenase enzyme was present in plasmid-positive clones, whereas detectable and significant activity of this enzyme was found in plasmid-negative clones. The lack of activity of the beta-isopropylmalate dehydrogenase enzyme is considered responsible for the L-leucine auxotrophy in the plasmid-positive clones.
Mattarelli
P
P
Istituto di Microbiologia Agraria, Bologna, Italy.
Biavati
B
B
D050539:3-Isopropylmalate Dehydrogenase; D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D001644:Bifidobacterium / Q000201:enzymology* / Q000254:growth & development; D003470:Culture Media / Q000737:chemistry; D045782:Hemiterpenes; D007651:Keto Acids / Q000378:metabolism; D007930:Leucine / Q000378:metabolism*; D010957:Plasmids
D003470:Culture Media; D045782:Hemiterpenes; D007651:Keto Acids; C001505:alpha-ketoisovalerate; C013082:alpha-ketoisocaproic acid; D000429:Alcohol Oxidoreductases; D050539:3-Isopropylmalate Dehydrogenase; D007930:Leucine