Physiological Aspects of Violacein Biosynthesis in Nonproliferating Cells

INCORPORATION OF C 14 -LABELED SUBSTRATES INTO VIOLACEIN

“…If pigment intermediates represent the source of unlabeled carbon, then it could be expected that cells grown in the presence of labeled tryptophan would accumulate the endogenous intermediates and incorporate them into pigment in an appropriate reaction mixture containing unlabeled tryptophan. This hypothesis was tested by growing cells in CV medium (DeMoss and Evans, 1959) containing DL-tryptophan-3'-C14 or DL-serine-3-C14. The labeled cells were harvested and exposed to unlabeled tryptophan under conditions which promoted pigment synthesis.…”

“…MATERIALS AND METHODS C. iiolaceum strain 553 was grown and harvested as previously described (DeMoss and Evans, 1959). Violacein synthesis by nonproliferating cells in the presence of C'4-labeled substrates formed the basis for incorporation studies.…”

“…The blue component was determined quantitatively by suitable dilution and measurement at 565 m,u in the Beckman model DU spectrophotometer. The extinction coefficient was previously determined to be approximately 17.0 X 106 cm2 per mole (DeMoss and Evans, 1959). After the quantity of blue pigment was determined, the ethanolic solution was evaporated to a small volume or to dryness and assayed for C'4 content.…”

Analise multivariada em N-modos

“…De Moss notou, também, que a quantidade de pigmento formada é proporcional a quantidade de L-triptofano presente no meio, da mesma forma que a velocidade de síntese da violaceína é diretamente proporcional à concentração de células. 138 N Rettori, foi encontrada uma proporção 9:1 de violaceína e deoxiviolaceina respectivamente no extrato obtido após extração com etanol absoluto. 139 Para a incorporação dos átomos de oxigênio a C. violaceum utiliza uma enzima oxigenase.…”