Selection and partial characterization of a Pseudomonas aeruginosa mono-rhamnolipid deficient mutant.
Pseudomonas aeruginosa produces rhamnolipids which are tenso-active compounds with potential industrial and environmental applications. There are two main types of rhamnolipids produced in liquid cultures, rhamnosyl-beta-hydroxydecanoyl-beta-hydroxydecanoate (mono-rhamnolipid) and rhamnosyl-rhamnosyl-beta-hydroxydecanoyl-beta-hydroxyd ecanoate (di-rhamnolipid). In this work we report the selective isolation of a rhamnolipid deficient mutant (IBT8), which does not accumulate mono-rhamnolipid while still producing di-rhamnolipid. IBT8 was selected after random mutagenesis with Tn501; yet, its mono-rhamnolipid deficiency was found associated neither with its Tn501 insertion nor with a possible alteration in the rhlABRI genes for rhamnosyl-transferase 1 synthesis. Different possibilities to explain IBT8 phenotype are discussed.
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Departamento de Microbiología Molecular, Universidad Nacional Autónoma de México, Cuernavaca, Mor., Mexico.
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Hernández
A L
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Miller
R M
RM
Soberón-Chávez
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D001426:Bacterial Proteins / Q000235:genetics; D003651:Decanoates / Q000378:metabolism*; D005798:Genes, Bacterial; D006017:Glycolipids / Q000096:biosynthesis*; D006602:Hexosyltransferases / Q000235:genetics; D016254:Mutagenesis, Insertional; D009154:Mutation; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000378:metabolism*; D012210:Rhamnose / Q000031:analogs & derivatives* / Q000378:metabolism
D001426:Bacterial Proteins; D003651:Decanoates; D006017:Glycolipids; C086515:RhlR protein, Pseudomonas aeruginosa; C051310:rhamnolipid hemolysin, Pseudomonas aeruginosa; C085734:rhamnopyranosyl-3-hydroxydecanoyl-3-hydroxydecanoate; D006602:Hexosyltransferases; C088697:rhamnosyltransferase 1; D012210:Rhamnose