RESUMO
1. The HCl-methanol (HCl-MeOH) soluble fraction from the puparial cuticle of yellow, black and ebony of D. melanogaster was hydrolyzed in hydrochloric acid and examined for beta-alanine, ketocatechol, and acetic acid. 2. Between beta-alanine and ketocatechol and between beta-alanine and acetic acid, a quantitatively inverse relationship was found, respectively. The former relationship was further confirmed by the feeding experiment of beta-alanine to black. 3. Of total beta-alanine in the HCl-MeOH extract, the proportion of those having free amino group was 74.8 per cent. 4. All these results indicate that the HCl-MeOH soluble fraction of the puparial cuticle may be useful for investigating the cross-link structure of the cuticle.
Assuntos
Drosophila melanogaster/química , Acetatos/análise , Animais , Catecóis/análise , Extratos Celulares , Drosophila melanogaster/citologia , Drosophila melanogaster/embriologia , Ácido Clorídrico , Metanol , Pupa/química , Análise Espectral , beta-Alanina/análiseRESUMO
Papiliochrome II is a pale yellow pigment of butterflies and consists of one molecule each ofL-kynurenine and N-ß-alanyldopamine (NBAD). The aromatic amino nitrogen of kynurenine is bonded to theß-carbon of NBAD. There are isomers IIa and IIb which show opposite circular dichroism. Theß-alanine contents of IIa and IIb were determined and the molar ratio of IIa to IIb has proved to be 1.17. The IIa and IIb were decomposed toL-kynurenine and N-ß-alanylnorepinephrine (NBANE) by being heated in water at 80°C for 30 min. In both IIa and IIb, circular dichroism of the NBANE showed the same positive peak at 280 nm. The NBANE were further decomposed toß-alanine and norepinephrine (NE) by being heated in 1 N HC1 at 100°C for 2 hr. The NE was submitted to enantioseparation and has proved to be a racemic mixture in both cases of IIa and IIb. These results are discussed in the light of the enzymic synthesis of IIa and IIb.
RESUMO
The yellow pigment (Papiliochrome II) of the wings of Papilio xuthus (papilionid butterfly) were extracted, purified with column chromatographies, and examined for chemical and physical properties. Furthermore, the decomposition-products of the pigment were isolated with columm chromatographies and identified. It was found that the pigment readily decomposed on heating to a DOPAmine derivative (SN-1) and kynurenine and that the SN-1 substance was broken down into a DOPAmine derivative (SN-1a) and beta-alanine by hydrolysis in 1 N HCl. These results were confirmed by the injection-experiments of 14C-tryptophan, 14C-DOPAmine, and 14C-beta-alanine. It has been concluded that Papilio-chrome II contains a beta-alanyl DOPAmine derivative and kynurenine as constituents.
