Keratins are the widely distributed fibrous proteins of our environment. Keratinase are proteolytic enzymes responsible for hydrolyzing insoluble keratin largely produced by microorganisms including ...fungi. The isolation, identification and characterization of a non-dermatophytic keratinolytic fungal strain of Cochliobolus lunatus from the soils of Khairpur Sindh Pakistan were reported. The temperature optimum for this strain production of the enzyme was 30 degree C, preferable carbon and nitrogen sources were glucose and gelatin respectively, optimum time for keratinase production was 9 days and the activity was suppressed by Ca super(2+) ions.
Salinity stress can severely affect the growth and production of the crop plants. Cheap and reliable actions are needed to enable the crop plants to grow normal under saline conditions. Modification ...at the molecular level to produce resistant cultivars is one of the promising, yet highly expensive techniques, whereas application of endophytes on the other hand are very cheap. In this regard, the role of Cochliobolus sp. in alleviating NaCl-induced stress in okra has been investigated. The growth and biomass yield, relative water content, chlorophyll content and IAA were decreased, whereas malondialdehyde (MDA) and proline content were increased in okra plants treated with 100 mM NaCl. On the contrary, okra plants inoculated with C. lunatus had higher shoot length, root length, plant dry weight, chlorophyll, carotenoids, xanthophyll, phenolicss, flavonoids, IAA, total soluble sugar and relative water content, while lower MDA. LC-MS/MS analysis of the Cochliobolus sp. extract revealed the presence of pinocembrin, chlorogenic acids, wogonin, calycosin and diadzein as a salinity stress reliever. From the results, it can be concluded that colonization of Cochliobolus sp. improves the NaCl tolerance by ameliorating the physicochemical attributes of the host plants.
•A potent entophytic fungus isolated from the Mirabilis jalapa was tested for plant growth promotion in okra plants under salinity stress.•The exogenous supply of Cochliobolus sp. supported the okra plants under salinity by influencing the plant endogenous hormones and biomolecules.•The Cochliobolus sp. acted as a salt stress reliever in okra plants indicated that it can be used as bio-fertilizer to grow crops in saline areas.
During the winter season of 2011, Cochliobolus lunatus was isolated from necrotized leaves of potato in potato plantations of Burdwan District, West Bengal State, India. The isolate was identified ...using standard monographs and taxonomic keys and confirmed molecularly using the Ribosomal Deoxyribonucleic acid (rDNA) sequence data. The Koch's postulate was confirmed through pathogenicity test on potato cultivar 'Kufri Jyoti'. This is the first report of C. lunatus causing brown-to-black spots disease of potato in India.
(anamorph:
) is a major pathogenic fungus that causes the Curvularia leaf spot of maize.
and
, the
orthologs of
and
, were investigated in the present study to uncover their functions in
. Southern ...blot analysis showed that these mating-type
genes exist in the
genome as a single copy.
and
were knocked out and complemented to generate Δ
and Δ
and Δ
C and Δ
C, respectively. The mutant strains had defective sexual development and failed to produce pseudothecia. There were no significant differences in growth rate or conidia production between the mutant and wild-type strains. However, the aerial mycelia and mycelial dry weight of Δ
and Δ
were lower than those of wild type, suggesting that
genes affect asexual development.
genes were involved in the responses to cell wall integrity and osmotic adaptation. Δ
had a lower conidial germination rate than the wild-type strain CX-3. The virulence of Δ
and Δ
was also reduced compared with the wild-type. Complementary strains could restore all the phenotypes.
Chemical epigenetic manipulation was applied to the marine-derived fungus Cochliobolus lunatus (TA26-46) with histone deacetylase inhibitors, resulting in significant changes of the secondary ...metabolites. Two new 14-membered resorcylic acid lactones characterized with bromine substitution, 5-bromozeaenol (1) and 3,5-dibromozeaenol (2), together with four known analogues (3–6), were isolated from the culture treated with sodium butyrate. The absolute configurations of 1 and 2 were assigned by CD spectra and chemical conversion. Compounds 1 and 2 represent the first example of natural brominated resorcylic acid lactones. These brominated lactones were exclusively obtained from C. lunatus (TA26-46) following epigenetic modifying treatments.
The 14α-hydroxysteroids have specific anti-gonadotropic and carcinolytic biological activities and can be produced by microbial biotransformation. The steroid 11β-/14α-hydroxylase
P
-450
lun
from
...Cochliobolus lunatus
is the only fungal cytochrome P450 enzyme identified to date with steroid C14 hydroxylation ability. Previous work has mainly revealed the 11β-hydroxylation activity of the
P
-450
lun
towards cortexolone (RSS) substrate; however, the potential steroid 14α-hydroxylation activity of this enzyme, especially for androstenedione (AD) substrate, has not yet conducted in-depth testing. In this work, we further tested the steroid 14α-hydroxylation activity of the
P
-450
lun
towards RSS and AD in the
Saccharomyces cerevisiae
system. We demonstrated that
P
-450
lun
functions as the specific 14α-hydroxylase towards the AD substrate (regiospecificity > 99%); however, it showed a poor C14-hydroxylation regiospecificity (around 40%) for the RSS substrate. In addition, through transcriptome analysis combined with gene functional characterizations, we also identified and cloned the gene for the
P
-450
lun
-associated redox partner CPR
lun
. Finally, through codon optimization, knockout of genes for the side reactions related enzymes GCY1 and YPR1, and increasing copies of the
P-450
lun
and
CPR
lun
, we developed a recombinant
S
.
cerevisiae
biocatalyst based on the
C
.
lunatus
steroid 14α-hydroxylation system to produce 14α-hydroxysteroids. Initial production of 14α-OH-AD (150 mg/L day productivity, 99% regioisomeric purity, and 60% w/w yield) and 14α-OH-RSS (64 mg/L day productivity, 40% regioisomeric purity, and 26% w/w yield) were separately achieved in shake flasks; these results represent the highest level of 14α-hydroxysteroid production in the current yeast system.
Three new 14-membered resorcylic acid lactones, cochliomycins D–F, 1–3, and eight known analogues, 4–11, were isolated from the sea anemone-derived fungus Cochliobolus lunatus. Compounds 1–4 are ...diastereomers differing from each other by the absolute configurations of the 4′,5′-diol chiral centers. The absolute configurations of 1–4 were established by the CD exciton chirality method and TDDFT ECD calculations. In antifouling assays, 1, 3–6, and 6a exhibited potent antifouling activities against the larval settlement of the barnacle Balanus amphitrite at nontoxic concentrations, with EC50 values ranging from 1.82 to 22.5 μg/mL. Noticeably, fungicide whole-plant assays indicated that 6 showed excellent activity on the Plasmopara viticola preventative test at 6 ppm and concentration-dependent activity on the Phytophthora infestans preventative application at 200, 60, and 20 ppm. Preliminary structure–activity relationships are also discussed.
The zoanthid-derived fungus
Cochliobolus lunatus
(TA26-46) has been proven to be a source of bioactive 14-membered resorcylic acid lactones (RALs). In the present study, chemical epigenetic ...manipulation was applied to this fungal strain with a DNA methyltransferase inhibitor resulting in the significant changes of the secondary metabolites. Cultivation of
C. lunatus
(TA26-46) with 10 μM 5-azacytidine in Czapek-Dox liquid medium led to the isolation of new types of metabolites, including two α-pyrones, cochliobopyrones A (
1
) and B (
2
), along with three isocoumarins (
3
–
5
) and one chromone (
6
). The planar structures of the new compounds (
1
–
2
) were elucidated by comprehensive analyses of NMR and HRESIMS data. Their challenging relative configurations were established by a combination of acetonide reaction, coupling constants and NOESY correlations analysis, and DP4+ probability calculation. Their absolute configurations were determined by comparing with the ECD calculation data of the fragment molecules, 6-(1,2-dihydroxypropyl)-4-methoxy-2
H
-pyran-2-ones. It is the first time to obtain α
-pyrone
compounds with the epoxy ring or bromine atom on the seven-numbered side chain. It could be concluded that chemical epigenetic agents could induce
C. lunatus
to produce new types of secondary metabolites differing from its original products (RALs).
AIMS: CYP53A15, from the sorghum pathogen Cochliobolus lunatus, is involved in detoxification of benzoate, a key intermediate in aromatic compound metabolism in fungi. Because this enzyme is unique ...to fungi, it is a promising drug target in fungal pathogens of other eukaryotes. METHODS AND RESULTS: In our work, we showed high antifungal activity of seven cinnamic acid derivatives against C. lunatus and two other fungi, Aspergillus niger and Pleurotus ostreatus. To elucidate the mechanism of action of cinnamic acid derivatives with the most potent antifungal properties, we studied the interactions between these compounds and the active site of C. lunatus cytochrome P450, CYP53A15. CONCLUSION: We demonstrated that cinnamic acid and at least four of the 42 tested derivatives inhibit CYP53A15 enzymatic activity. SIGNIFICANCE AND IMPACT OF THE STUDY: By identifying selected derivatives of cinnamic acid as possible antifungal drugs, and CYP53 family enzymes as their targets, we revealed a potential inhibitor‐target system for antifungal drug development.
A pair of novel lipopeptide epimers, sinulariapeptides A (
) and B (
), and a new phthalide glycerol ether (
) were isolated from the marine algal-associated fungus
SCSIO41401, together with three ...known chromanone derivates (
-
). The structures of the new compounds, including the absolute configurations, were determined by comprehensive spectroscopic methods, experimental and calculated electronic circular dichroism (ECD), and Mo
(OAc)
-induced ECD methods. The new compounds
-
showed moderate inhibitory activity against acetylcholinesterase (AChE), with IC
values of 1.3-2.5 μM, and an in silico molecular docking study was also performed.
PDF
