3 research outputs found
The Asymmetric Total Synthesis of Cinbotolide: A Revision of the Original Structure
The
structure 3,4-dihydroxy-2,4,6,8-tetramethyldec-8-enolide (<b>1</b>) was assigned to a metabolite of <i>Botrytis
cinerea</i>, but the spectra of several
synthetic analogues had significant differences from that of <b>1</b>. Examination of the constituents of a <i>B. cinerea</i> mutant that overproduces polyketides gave sufficient quantities
of <b>1</b>, now named cinbotolide, for chemical transformations.
These led to a revised γ-butyrolactone structure for the metabolite.
This structure has been confirmed by an asymmetric total synthesis,
which also established its absolute configuration
Phytotoxic Activity and Metabolism of <i>Botrytis cinerea</i> and Structure–Activity Relationships of Isocaryolane Derivatives
Research has been conducted on the
biotransformation of (8<i>S</i>,9<i>R</i>)-isocaryolan-9-ol
(<b>4a</b>) and (1<i>S</i>,2<i>S</i>,5<i>R</i>,8<i>S</i>)-8-methylene-1,4,4-trimethyltricyclo[6.2.1.0<sup>2,5</sup>]undecan-12-ol (<b>5a</b>) by the fungal phytopathogen <i>Botrytis cinerea</i>. The biotransformation of compound <b>4a</b> yielded compounds <b>6</b>–<b>9</b>,
while the biotransformation of compound <b>5a</b> yielded compounds <b>10</b>–<b>13</b>. The activity of compounds <b>4a</b> and <b>5a</b> against <i>B. cinerea</i> has been evaluated. (8<i>R</i>,9<i>R</i>)-Isocaryolane-8,9-diol
(<b>6</b>), a major metabolite of compound <b>4a</b>,
shows activity compared to its parent compound <b>4a</b>, which
is inactive. The effect of isocaryolanes <b>3</b>, <b>4a</b>, and <b>5a</b>, together with their biotransformation products <b>6</b>–<b>8</b>, <b>10</b>, and <b>14</b>–<b>17</b>, on the germination and radicle and shoot
growth of <i>Lactuca sativa</i> (lettuce) has also been
determined. Compounds <b>7</b>–<b>13</b> are described
for the first time
Chemically Induced Cryptic Sesquiterpenoids and Expression of Sesquiterpene Cyclases in <i>Botrytis cinerea</i> Revealed New Sporogenic (+)-4-<i>Epi</i>eremophil-9-en-11-ols
The
sequencing of the genomes of the B05.10 and T4 strains of the
fungus <i>Botrytis cinerea</i> revealed an abundance of
novel biosynthetic gene clusters, the majority of which were unexpected
on the basis of the previous analyses of the fermentation of these
and closely related species. By systematic alteration of easy accessible
cultivation parameters, using chemical induction with copper sulfate,
we have found a cryptic sesquiterpenoid family with new structures
related to eremophil-9-ene, which had the basic structure of the sesquiterpene
(+)-5-<i>epi</i>aristolochene ((+)-4-<i>epi</i>eremophil-9-ene). An expression study of the sesquiterpene cyclase
genes present in the <i>Botrytis cinerea</i> genome, under
culture conditions, is reported. In general, a 3 day delay and a higher <i>BcSTC</i> genes expression were observed when copper (5 ppm)
was fed to the fermentation broth. In addition, to the observed effect
on the <i>BcBOT2</i> (<i>BcSTC1</i>) gene, involved
in the biosynthesis of the botrydial toxin, a higher expression level
for <i>BcSTC3</i> and <i>BcSTC4</i> was observed
with respect to the control in the strain B05.10. Interestingly, under
copper conditions, the <i>BcSTC4</i> gene was the most expressed
gene in the <i>Botrytis cinerea</i> UCA992 strain. <i>In vitro</i> evaluation of the biological role of these metabolites
indicates that they contributed to the conidial development in <i>B. cinerea</i> and appear to be involved in self-regulation
of the production of asexual spores. Furthermore, they promoted the
formation of complex appressoria or infection cushions