The protein encoded by the Shewanella colwellianamelA gene is a p-hydroxyphenylpyruvate dioxygenase

Abstract

The identity of the product of the melA gene from Shewanella colelliana with the enzyme p‐hydroxyphenylpyruvic dioxygenase is shown. Cloning of the melA gene endowed Escherichia coli with the capacity to synthesize melanin‐like pigments from L‐tyrosine. E. coli contained transaminases that transforms L‐tyrosine into p‐hydroxyphenylpyruvate. This keto acid was detected in the cultures. On the other hand, E. coli containing melA was able to go further in the catabolic pathway, releasing a great amount of homogentisic acid. This acid can spontaneously polymerize giving the pigment. Furthermore, p‐hydroxyphenylpyruvate dioxygenase activity was detected in this system. Analysis of the deduced amino acid sequence revealed a high homology with the p‐hydroxyphenylpyruvate deoxygenase enzyme from different organisms.

The C‐terminal of rat 4‐hydroxyphenylpyruvate dioxygenase is indispensable for enzyme activity

“…As noticed by other groups cloning 4HPPD from Streptomyces avermitilis and melA gene from Shewanella colwelliana, E. coli harboring the plasmid containing the 4HPPD gene produced a characteristic brownish pigment after overnight culture both on solid and liquid media [16,7]. The authors found that the intensity of this pigment could be increased by the addition of L-tyrosine.…”

“…culture both on solid and liquid media [16,7]. The authors found that the intensity of this pigment could be increased by the addition of L-tyrosine.…”

“…As an important enzyme in the degradation pathway of tyrosine, inhibition of 4HPPD has been used in the treatment of tyrosinaemia (type I) and liver cirrhosis [5]. It has also been demonstrated that 4HPPD is involved in the formation of melanin-like pigment in marine bacteria [6,7]. Most interestingly, we recently found that 4HPPD purified from rat liver is capable of catalysing the conversion of ~¢-ketoisocaproate (ecKIC) to [3-hydroxyisovaleric acid [8].…”

The role of 4-hydroxyphenylpyruvate dioxygenase in enhancement of solid-phase electron transfer by Shewanella oneidensis MR-1

“…Because Fe(II) inhibits 4‐HPPD and pyomelanin production (Lindblad et al , 1977; Turick et al , 2008a, b), Fe(III) was not used as a terminal electron acceptor. The resultant pigment, pyomelanin, is also produced by Shewanella collwelliana (Fuqua & Weiner, 1993; Ruzafa et al , 1994) and S. algae BrY (Turick et al , 2002, 2003). The absence of HGD or its decreased activity relative to 4‐HPPD results in the overproduction of homogentisate, ultimately leading to extracellular pyomelanin formation.…”

“…There are several different types of melanin pigments produced by microorganisms (Prota, 1992). One particular type of melanin, pyomelanin, originates from the conversion of tyrosine and/or phenylalanine as part of the fumarate pathway (Lehninger, 1975), and is found in numerous bacterial genera (Yabuuchi & Omyama, 1972; Kotob et al , 1995; Ruzafa et al , 1995; David et al , 1996; Sanchez‐Amat et al , 1998), including Shewanella (Fuqua & Weiner, 1993; Coon et al , 1994; Ruzafa et al , 1994; Turick et al , 2002, 2008a), Legionella (Chatfield & Cianciotto, 2007) and Burkholderia (Zughaier et al , 1999). Complete breakdown of these amino acids to acetoacetate and fumarate requires the activities of 4‐hydroxyphenylpyruvate dioxygenase (4‐HPPD) and homogentisate oxidase (Fuqua & Weiner, 1993; David et al , 1996).…”