Conversion of 4-γ,γ-dimethylallyltryptophan to clavicipitic acid. Some properties of the enzyme

The particle-bound enzyme catalysing the conversion of dl-4-γ,γ-diinethylallyltryptophan into clavicipitic acid in Claviceps purpurea PRL 1980 has been solubilised. The K_m value and pH optimum were determined and the substrate specfficity of the enzyme and the effect of inhibitors were studied. The racemisation of l-tryptophan in the culture medium was investigated.     

Cell-free conversion of 4-γ,γ-dimethylallyltryptophan to 4-[4-hydroxy-3-methyl-Δ2-butenyl]-tryptophan in Claviceps purpurea PRL 1980

The conversion of 4-γ,γ-dimethylallyltryptophan to 4-[4-hydroxy-3-methyl-Δ²-butenyl]-tryptophan was catalyzed by the 60–80% ammonium sulphate fraction from Claviceps purpurea PRL 1980. The conversion was stimulated by NADPH. Two major unidentified products in the incubation mixture were not significantly incorporated into elymoclavine when they were added to cultures of C. purpurea PRL 1980.     

5-hydroxytryptophan and soluble pigment formation in Claviceps sp. PRL 1980

5-Hydroxytryptophan (156 mg/l) was identified in 15-day-old cultures of Claviceps sp. PRL 1980. [side-chain 3-¹⁴C] dl-Tryptophan and [side-chain 3-¹⁴C] 5-hydroxytryptophan were incorporated into the brown pigment in cultures of the same fungus, 6% and 24%, respectively.     

N-acetyl-L-tryptophan in Claviceps purpurea PRL 1980

Claviceps purpurpea PRL 1980 converts L-tryptophan to N-acetyl-L-trytophan. There is little acetylation of D-tryptophan. Added N-acetyl-L -trypotophan. has no effect on alkaloid production. L-Tyrosine addition results in production of a compound which is probably N-acetyltyrosine and also causes accumulation of 4-γ,γ-dimethylally-tryptophan.     

Microsomal agroclavine hydroxylase of Claviceps species

[4-¹⁴C]Agroclavine was converted to elymoclavine in the presence of NADPH and the microsomal fraction from Claviceps sp. PRL 1980 and SD 58. Th     

Parasitic fungus Claviceps as a source for biotechnological production of ergot alkaloids

Ergot alkaloids produced by the fungus Claviceps parasitizing on cereals, include three major groups: clavine alkaloids, d-lysergic acid and its derivatives and ergopeptines. These alkaloids are important substances for the pharmatech industry, where they are used for production of anti-migraine drugs, uterotonics, prolactin inhibitors, anti-Parkinson agents, etc. Production of ergot alkaloids is based either on traditional field cultivation of ergot-infected rye or on submerged cultures of the fungus in industrial fermentation plants. In 2010, the total production of these alkaloids in the world was about 20,000 kg, of which field cultivation contributed about 50%. This review covers the recent advances in understanding of the genetics and regulation of biosynthesis of ergot alkaloids, focusing on possible applications of the new knowledge to improve the production yield.     

New alkaloids from Strychnos icaja

The alkaloids of Strychnos icaja (Loganiaceae) have been studied. An extract from Zaire leaf material yielded nine alkaloids, comprising novacine, the new base 21,22-α-epoxy-4,14-dihydroxy-3-methoxy-N-methyl-sec.-pseudostrychnine, and seven others of known structure previously obtained from the plant. Cameroun leaf material gave five alkaloids, of which one, 21,22-α-epoxy-3,4-dimethoxy-N-methyl-sec.-pseudostrychnine, is new. Fruits from Gabon afforded eight alkaloids; two of them are new and are formulated as 21,22-α-epoxy-4-methoxy-N-methyl-sec.-pseudostrychnine and the corresponding 14-hydroxy derivative.     

Formation of alkaloids in Corydalis ophiocarpa callus culture

Corydalis ophiocarpa callus tissue was examined for its isoquinoline alkaloid content. The culture has good biosynthetic capabilities for transformation of exogenous alkaloids.     

Formation of acetyltropine in Datura callus cultures

The production of tropoylesters in suspension cultures of Datura innoxia stem callus was significantly stimulated by dl-tropic acid, phenylpyruvate or tropine, but was little affected by l-phenylalanine or l-ornithine. Analyses have shown that acetyltropine is synthesized in large quantities by cultured cells when tropine has been supplied to various cultures of D. innoxia and D. tatula. Acetyltropine has been isolated from either the culture medium or cells supplied with tropine. These results indicate that tropine absorbed by the cultured cells of Datura is esterified predominantly by acetic acid to form acetyltropine, instead of other tropane alkaloids.     

Distribution of alkaloids in Anthocercis littorea and A. viscosa

The distribution of tropane alkaloids in organs of Anthocercis littorea and A. viscosa is reported. The following alkaloids have been isolated: atropine (hyoscyamine), apoatropine, noratropine (norhyoscyamine), littorine, hyoscine, norhyoscine, meteloidine, 3α, 6β-ditigloyloxytropan-7β-ol, 6β-tigloyloxytropan-3α-ol, 3α-tigloyloxytropane, tigloidine, tropine, ψ-tropine, (?)-tropan-3α-6β-diol, cuscohygrine and unknown bases.     

Enzymic reduction of codeinone in vitro cell-free systems from Papaver somniferum and P. Bracteatum

Cell-free extracts have been prepared from Papaver somniferum which catalyze the reduction of codeinone-[16-³H] to codeine. The methodology for examining this conversion has pointed to conditions for exploring the preparation of suitable enzyme extracts. P. bracteatum also yielded a cell-free system which reduced codeinone to codeine, both of which are foreign to this species.     

Peptide alkaloids of Scutia buxifolia

Two new components, the peptide alkaloid scutianine D and scutianene C have been isolated from Scutia buxifolia and their structures elucidated. The configuration of some of the asymmetric centers of scutianine A has been determined by gas chromatography.     

Hydroxytropane tiglates in the roots of Mandragora species

Roots of Mandragora autumnalis and M. vernalis contain hyoscyamine, hyoscine, cuscohygrine, apoatropine 3α-tigloyloxytropane and 3,6-ditigloyloxytropane. Belladonnine is present in the dried roots but could not be detected in fresh roots. No major differences were found in the alkaloids present in the two species. This is the first time the presence of tiglic acid esters has been reported in Mandragora species and the significance of this in the chemotaxonomy of the genus is indicated.     

Aristololactams of Aristolochia argentina

Four new lactams have been isolated and characterized from the roots of Aristolochia argentina.     

New organic bases from amazonian Banisteriopsis caapi

Three new bases were isolated from Banisteriopsis caapi; they are harmine N-oxide, harmic acid methyl ester (methyl 7-methoxy-β-carboline 1-carboxylate) and harmalinic acid (7-methoxy-3,4-dihydro-β-carboline 1-carboxylic acid).     

Gluconacetobacter maltaceti sp. nov., a novel vinegar producing acetic acid bacterium

Comparison of HaeIII- and HpaII-restriction profiles of PCR-amplified 16S-23S rDNA ITS regions of Gluconacetobacter sp. LMG 1529^T and SKU 1109 with restriction profiles of reference strains of acetic acid bacteria described by Tr?ek and Teuber [34] revealed the same but unique restriction profiles for LMG 1529^T and SKU 1109. Further analyses of nearly complete 16S rRNA gene sequences, nearly complete 16S-23S rDNA ITS sequences, as well as concatenated partial sequences of the housekeeping genes dnaK, groEL and rpoB, allocated both strains to a single phylogenetic cluster well separated from the other species of the genus Gluconacetobacter. DNA–DNA hybridizations confirmed their novel species identity by 73% DNA–DNA relatedness between both strains, and values below the species level (<70%) between SKU 1109 and the type strains of the closest phylogenetic neighbors. The classification of strains LMG 1529^T and SKU 1109 into a single novel species was confirmed also by AFLP and (GTG)₅-PCR DNA fingerprinting data, as well as by phenotypic data. Strains LMG 1529^T and SKU 1109 can be differentiated from their closely related Gluconacetobacter species, Gluconacetobacter entanii and Gluconacetobacter hansenii, by their ability to form 2-keto-d-gluconic acid from d-glucose, their ability to use d-mannitol, d-gluconate and glycerol as carbon source and form acid from d-fructose, and their ability to grow without acetic acid. The major fatty acid of LMG 1529^T and SKU 1109 is C_18:1ω7c (60.2–64.8%). The DNA G + C content of LMG 1529^T and SKU 1109 is 62.5 and 63.3 mol% respectively. The name Gluconacetobacter maltaceti sp. nov. is proposed. The type strain is LMG 1529^T (= NBRC 14815^T = NCIMB 8752^T).     

In vitro auxin production by Balansia epichloë

Balansia epichloë, a systemic plant pathogen isolated from Sporobolus poiretii, was shown to produce the plant growth regulators 3-indole acetic acid, 3-indole ethanol, 3-indole acetamide and methyl-3-indole carboxylate when grown on a medium containing tryptophan. When grown on a tryptophan deficient medium 3-substituted indole derivatives were not detected. However, extracts of the medium in lower doses increased and in higher doses inhibited the growth of wheat coleoptiles.     

Origin of cyclohexanecarboxylic acid in Bacillus acidocaldarius

In Bacillus acidocaldarius, shikimic acid is converted into the cyclohexancearboxylic acid precursor of fatty acids by way of cyclohexene-l-carboxylic acid, but not by way of cyclohexene-3- or -4-carboxylic acid or benzoic acid.