Clerodenoids A–F: C‐ring Aromatized and/or Rearranged Abietane Diterpenoids from Clerodendrum chinense var. simplex

ABSTRACT We have cloned and sequenced the dit gene cluster encoding enzymes of the catabolic pathway for abietane diterpenoid degradation by Pseudomonas abietaniphila BKME-9. Thedit gene cluster is located on a 16.7-kb DNA fragment containing 13 complete open reading frames (ORFs) and 1 partial ORF. The genes ditA1A2A3 encode the α and β subunits and the ferredoxin of the dioxygenase which hydroxylates 7-oxodehydroabietic acid to 7-oxo-11,12-dihydroxy-8,13-abietadien acid. The dioxygenase mutant strain BKME-941 (ditA1::Tn5) did not grow on nonaromatic abietanes, and transformed palustric and abietic acids to 7-oxodehydroabietic acid in cell suspension assays. Thus, nonaromatic abietanes are aromatized prior to further degradation. Catechol 2,3-dioxygenase activity of xylEtranscriptional fusion strains showed induction of ditA1and ditA3 by abietic, dehydroabietic, and 7-oxodehydroabietic acids, which support the growth of strain BKME-9, as well as by isopimaric and 12,14-dichlorodehydroabietic acids, which are diterpenoids that do not support the growth of strain BKME-9. In addition to the aromatic-ring-hydroxylating dioxygenase genes, thedit cluster includes ditC, encoding an extradiol ring cleavage dioxygenase, and ditR, encoding an IclR-type transcriptional regulator. Although ditR is not strictly required for the growth of strain BKME-9 on abietanes, aditR::Kmr mutation in aditA3::xylE reporter strain demonstrated that it encodes an inducer-dependent transcriptional activator of ditA3. An ORF with sequence similarity to genes encoding permeases (ditE) is linked with genes involved in abietane degradation.

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Cupriavidus metallidurans Strains with Different Mobilomes and from Distinct Environments Have Comparable Phenomes

Genes ◽

10.3390/genes9100507 ◽

2018 ◽

Vol 9 (10) ◽

pp. 507 ◽

Cited By ~ 5

Author(s):

Rob Van Houdt ◽

Ann Provoost ◽

Ado Van Assche ◽

Natalie Leys ◽

Bart Lievens ◽

...

Keyword(s):

Genomic Island ◽

Space Station ◽

Nutrient Utilization ◽

Metal Resistance ◽

Human Infection ◽

Abietane Diterpenoids ◽

Cupriavidus Metallidurans ◽

Mobile Gene ◽

Phenotype Microarrays ◽

The Impact

Cupriavidus metallidurans has been mostly studied because of its resistance to numerous heavy metals and is increasingly being recovered from other environments not typified by metal contamination. They host a large and diverse mobile gene pool, next to their native megaplasmids. Here, we used comparative genomics and global metabolic comparison to assess the impact of the mobilome on growth capabilities, nutrient utilization, and sensitivity to chemicals of type strain CH34 and three isolates (NA1, NA4 and H1130). The latter were isolated from water sources aboard the International Space Station (NA1 and NA4) and from an invasive human infection (H1130). The mobilome was expanded as prophages were predicted in NA4 and H1130, and a genomic island putatively involved in abietane diterpenoids metabolism was identified in H1130. An active CRISPR-Cas system was identified in strain NA4, providing immunity to a plasmid that integrated in CH34 and NA1. No correlation between the mobilome and isolation environment was found. In addition, our comparison indicated that the metal resistance determinants and properties are conserved among these strains and thus maintained in these environments. Furthermore, all strains were highly resistant to a wide variety of chemicals, much broader than metals. Only minor differences were observed in the phenomes (measured by phenotype microarrays), despite the large difference in mobilomes and the variable (shared by two or three strains) and strain-specific genomes.

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Antimicrobial and antiparasitic abietane diterpenoids from Cupressus sempervirens

Research and Reports in Medicinal Chemistry ◽

10.2147/rrmc.s29902 ◽

2012 ◽

pp. 1 ◽

Cited By ~ 5

Author(s):

Muhammad Ilias ◽

Zhang ◽

Rahman ◽

Jain ◽

Jacob ◽

...

Keyword(s):

Cupressus Sempervirens ◽

Abietane Diterpenoids

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Labdane and Abietane Diterpenoids from Juniperus oblonga and Their Cytotoxic Activity

Molecules ◽

10.3390/molecules24081561 ◽

2019 ◽

Vol 24 (8) ◽

pp. 1561 ◽

Cited By ~ 1

Author(s):

Qiao ◽

Khutsishvili ◽

Alizade ◽

Atha ◽

Borris

Keyword(s):

Cell Lines ◽

Human Tumor ◽

2D Nmr ◽

Human Tumor Cell Lines ◽

Abietane Diterpenoids ◽

Whole Plant ◽

Phytochemical Investigation ◽

Ic50 Values ◽

First Time ◽

Mcf 7

A phytochemical investigation of the whole plant of Juniperus oblonga led to the isolationof one previously undescribed labdane diterpenoid, (4R,5S,9S,10R)‐13‐des‐ethyl‐13‐oxolabda‐8(17),11E‐dien‐19‐oic acid (1), together with nine known diterpenoids (2–3, 6–12), two lignans (4, 5),and a coumarin (13). The structures of all the compounds were elucidated on the basis ofspectrometric data, primarily one‐dimensional (1D)‐ and two‐dimensional (2D)‐NMR and massspectrometry. Electronic circular dichroism (ECD) calculations determined the absoluteconfiguration of 1. In addition, the isolated compounds were evaluated for their cytotoxic activityagainst three human tumor cell lines (HepG2, MCF‐7, and HeLa). 6,12‐Dihydroxyabieta‐5,8,11,13‐tetraen‐7‐one (6) showed moderate cytotoxicity against all three cell lines with IC50 values rangingfrom 24.41 μM to 58.39 μM and trilobinone (10) showed weaker activity with IC50 values rangingfrom 56.93 μM to 79.98 μM. None of the isolated diterpenoids have been previously reported fromJuniperus oblonga, and five compounds are here reported from the genus Juniperus for the first time.

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