TY - JOUR
T1 - The gene carD encodes the aldehyde dehydrogenase responsible for neurosporaxanthin biosynthesis in Fusarium fujikuroi
AU - Díaz-Sánchez, Violeta
AU - Estrada, Alejandro F.
AU - Trautmann, Danika
AU - Al-Babili, Salim
AU - Avalos, Javier
PY - 2011/9
Y1 - 2011/9
N2 - Neurosporaxanthin (β-apo-4′-carotenoic acid) biosynthesis has been studied in detail in the fungus Fusarium fujikuroi. The genes and enzymes for this biosynthetic pathway are known until the last enzymatic step, the oxidation of the aldehyde group of its precursor, β-apo-4′-carotenal. On the basis of sequence homology to Neurospora crassa YLO-1, which mediates the formation of apo-4′-lycopenoic acid from the corresponding aldehyde substrate, we cloned the carD gene of F. fujikuroi and investigated the activity of the encoded enzyme. In vitro assays performed with heterologously expressed protein showed the formation of neurosporaxanthin and other apocarotenoid acids from the corresponding apocarotenals. To confirm this function in vivo, we generated an Escherichia coli strain producing β-apo-4′-carotenal, which was converted into neurosporaxanthin upon expression of carD. Moreover, the carD function was substantiated by its targeted disruption in a F. fujikuroi carotenoid-overproducing strain, which resulted in the loss of neurosporaxanthin and the accumulation of β-apo-4′-carotenal, its derivative β-apo-4′-carotenol, and minor amounts of other carotenoids. Intermediates accumulated in the ÎcarD mutant suggest that the reactions leading to neurosporaxanthin in Neurospora and Fusarium are different in their order. In contrast to ylo-1 in N. crassa, carD mRNA content is enhanced by light, but to a lesser extent than other enzymatic genes of the F. fujikuroi carotenoid pathway. Furthermore, carD mRNA levels were higher in carotenoid-overproducing mutants, supporting a functional role for CarD in F. fujikuroi carotenogenesis. With the genetic and biochemical characterization of CarD, the whole neurosporaxanthin biosynthetic pathway of F. fujikuroi has been established.
AB - Neurosporaxanthin (β-apo-4′-carotenoic acid) biosynthesis has been studied in detail in the fungus Fusarium fujikuroi. The genes and enzymes for this biosynthetic pathway are known until the last enzymatic step, the oxidation of the aldehyde group of its precursor, β-apo-4′-carotenal. On the basis of sequence homology to Neurospora crassa YLO-1, which mediates the formation of apo-4′-lycopenoic acid from the corresponding aldehyde substrate, we cloned the carD gene of F. fujikuroi and investigated the activity of the encoded enzyme. In vitro assays performed with heterologously expressed protein showed the formation of neurosporaxanthin and other apocarotenoid acids from the corresponding apocarotenals. To confirm this function in vivo, we generated an Escherichia coli strain producing β-apo-4′-carotenal, which was converted into neurosporaxanthin upon expression of carD. Moreover, the carD function was substantiated by its targeted disruption in a F. fujikuroi carotenoid-overproducing strain, which resulted in the loss of neurosporaxanthin and the accumulation of β-apo-4′-carotenal, its derivative β-apo-4′-carotenol, and minor amounts of other carotenoids. Intermediates accumulated in the ÎcarD mutant suggest that the reactions leading to neurosporaxanthin in Neurospora and Fusarium are different in their order. In contrast to ylo-1 in N. crassa, carD mRNA content is enhanced by light, but to a lesser extent than other enzymatic genes of the F. fujikuroi carotenoid pathway. Furthermore, carD mRNA levels were higher in carotenoid-overproducing mutants, supporting a functional role for CarD in F. fujikuroi carotenogenesis. With the genetic and biochemical characterization of CarD, the whole neurosporaxanthin biosynthetic pathway of F. fujikuroi has been established.
KW - apocarotenoids
KW - carS mutants
KW - carotenogenesis
KW - light regulation
KW - β-apo-4′-carotenal
UR - http://www.scopus.com/inward/record.url?scp=84860390110&partnerID=8YFLogxK
U2 - 10.1111/j.1742-4658.2011.08242.x
DO - 10.1111/j.1742-4658.2011.08242.x
M3 - Article
C2 - 21749649
AN - SCOPUS:84860390110
SN - 1742-464X
VL - 278
SP - 3164
EP - 3176
JO - FEBS Journal
JF - FEBS Journal
IS - 17
ER -