Characterization of monoterpene biotransformation in two pseudomonads.
OBJECTIVE
To study the metabolic profile of Pseudomonas rhodesiae and Pseudomonas fluorescens in water-organic solvent systems using terpene substrates for both growth and biotransformation processes and to determine the aerobic or anaerobic status of these degradation pathways.


METHODS
Substrates from pinene (alpha-pinene, alpha-pinene oxide, beta-pinene, beta-pinene oxide, turpentine) and limonene (limonene, limonene-1,2-oxide, orange peel oil) families were tested. For the bioconversion, the terpene-grown biomass was concentrated and used either as whole cells or as a crude enzymatic extract.


CONCLUSIONS
Pseudomonas rhodesiae was the most suitable biocatalyst for the production of isonovalal from alpha-pinene oxide and did not metabolize limonene. Pseudomonas fluorescens was a more versatile micro-organism and metabolized limonene in two different ways. The first (anaerobic, cofactor-independent, noninducible) allowed limonene elimination by synthesizing alpha-terpineol. The second (aerobic, cofactor-dependent) involved limonene-1,2-oxide as an intermediate for energy production through a beta-oxidation process.


CONCLUSIONS
Enzymatic isomerization of beta- to alpha-pinene was described for the first time for both strains. Alpha-terpineol production by P. fluorescens was very efficient and appeared as a promising alternative for the commercial production of this bioflavour.
Bicas
J L
JL
Laboratório de Bioaromas, Departamento de Ciência de Alimentos-FEA, Universidade Estadual de Campinas, Rua Monteiro Lobato, Campinas-SP, Brasil. jlbicas@gmail.com
Fontanille
P
P
Pastore
G M
GM
Larroche
C
C
D000447:Aldehydes / Q000378:metabolism*; D001711:Biotransformation; D032084:Citrus sinensis; D053138:Cyclohexenes / Q000737:chemistry / Q000378:metabolism; D000077222:Limonene; D055442:Metabolome; D039821:Monoterpenes / Q000737:chemistry / Q000378:metabolism*; D010938:Plant Oils / Q000378:metabolism; D011549:Pseudomonas / Q000378:metabolism*; D011551:Pseudomonas fluorescens / Q000378:metabolism; D013729:Terpenes / Q000737:chemistry / Q000378:metabolism
D000447:Aldehydes; D053138:Cyclohexenes; D039821:Monoterpenes; D010938:Plant Oils; D013729:Terpenes; C473705:isonovalal; D000077222:Limonene