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The hydroxylation of tyrosine by an enzyme from third-instar larvae of the blowfly Calliphora erythrocephala.

ABSTRACT: 1. Two pro-(phenol oxidase) were distinguished when the blood of late-third-instar larvae of Calliphora erythrocephala was electrophoresed in polyacrylamide gels with Tris-glycine buffer, pH 8.3. One pro-(phenol oxidase), after activation by an enzyme readily catalyses the oxidation of both L-tyrosine and L-3,4-dihydroxyphenylalanine (L-dopa). The second enzyme catalyses the oxidation of L-dopa but not of L-tyrosoine. 2. One of the pro-(phenol oxidases) was purified over 2000-fold from homogenates of whole larvae. This enzyme, after activation, catalyses the oxidation of both dopa and tyrosine. On electrophoresis in polyacrylamide gels with Tris-glycine buffer, pH 8.3, it has the same mobility as the enzyme in the blood which catalyses the oxidation of both tyrosine and dopa. 3. The pro-(phenol oxidase)-activating enzyme was purified over 100-fold from homogenates of whole larvae. 4. The oxidation of L-tyrosine, in the presence of the activated purified phenol oxidase, reached a steady maximum rate after a lag period that was directly related to tyrosine concentration and inversely related to enzyme concentration. 5. The effect of the addition of electron donors on the lag period was studied. Dopa, dopamine (3,4-dihydroxyphenethylamine) and 2-amino-4-hydroxy-6,7-dimethyl-5,6,7,8-tetrahydropteridine are the most effective hydrogen donors. 3,4-Dihydroxybenzoic acid, the oxidation of which was not catalysed by the activated pro-(phenol oxidase), did not affect the lag period.

SUBMITTER: Pau RN

PROVIDER: S-EPMC1165484 | biostudies-other | 1975 Jun

REPOSITORIES: biostudies-other

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The isolation of an o-diphenal oxidase from third-instar larvae of the blowfly Calliphora erythrocephala.

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Characterization of the complete mitochondrial genome of the New Zealand parasitic blowfly <i>Calliphora vicina</i> (Insecta: Diptera: Calliphoridae).

Project description:In this study, the complete mitochondrial (mt) genome of the New Zealand parasitic blowfly Calliphora vicina (blue bottle blowfly) field strain NZ_CalVic_NP was generated using next-generation sequencing technology and annotated. The 16,518 bp mt genome consists of 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, and a 1689 bp non-coding region, similar to the two other available C. vicina and most metazoan mt genomes. Phylogenetic analysis showed that C. vicina NZ_CalVic_NP forms a monophyletic cluster with the remaining three Calliphorinae species. The complete mt genome sequence of C. vicina NZ_CalVic_NP is a resource to facilitate future species- and strain-level identification research and investigations into the evolutionary provenance within the Calliphoridae.

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Molecular and pharmacological characterization of serotonin 5-HT2? and 5-HT7 receptors in the salivary glands of the blowfly Calliphora vicina.

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| S-EPMC3493529 | biostudies-literature

Analysis of the transcriptome of blowfly Chrysomya megacephala (Fabricius) larvae in responses to different edible oils.

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Effective L-Tyrosine Hydroxylation by Native and Immobilized Tyrosinase.

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| S-EPMC5053437 | biostudies-literature

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