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פותח על ידי קלירמאש פתרונות בע"מ -
Morphological transitions governed by density dependence and lipoxygenase activity in Aspergillus flavus
Year:
2008
Authors :
הורוביץ, סיגל בראון
;
.
Volume :
74
Co-Authors:
Horowitz Brown, S., Department of Plant Pathology, University of Wisconsin - Madison, Madison, WI 53706-1598, United States
Zarnowski, R., Department of Medical Microbiology and Immunology, University of Wisconsin - Madison, 1550 Linden Dr., Madison, WI 53706-1598, United States
Sharpee, W.C., Department of Plant Pathology, University of Wisconsin - Madison, Madison, WI 53706-1598, United States
Keller, N.P., Department of Plant Pathology, University of Wisconsin - Madison, Madison, WI 53706-1598, United States, Department of Medical Microbiology and Immunology, University of Wisconsin - Madison, 1550 Linden Dr., Madison, WI 53706-1598, United States, 3476 Microbial Science Building, Department of Medical Microbiology and Immunology, UW - Madison, 1550 Linden Dr., Madison, WI 53706, United States
Facilitators :
From page:
5674
To page:
5685
(
Total pages:
12
)
Abstract:
Aspergillus flavus differentiates to produce asexual dispersing spores (conidia) or overwintering survival structures called sclerotia. Results described here show that these two processes are oppositely regulated by density-dependent mechanisms and that increasing the cell density (from 10 1 to 107 cells/plate) results in the lowest numbers of sclerotial and the highest numbers of conidial. Extract from spent medium of low-cell-density cultures induced a high-sclerotium-number phenotype, whereas high-cell-density extract increased conidiation. Density-dependent development is also modified by changes in lipid availability. Exogenous linoleic acid increased sclerotial production at intermediate cell densities (104 and 105 cells/plate), whereas oleic and linolenic acids inhibited sclerotium formation. Deletion of Aflox encoding a lipoxygenase (LOX) greatly diminished density-dependent development of both sclerotia and conidia, resulting in an overall increase in the number of sclerotia and a decrease in the number of conidia at high cell densities (>105 cells/plate). Aflox mutants showed decreased linoleic acid LOX activity. Taken together, these results suggest that there is a quorum-sensing mechanism in which a factor(s) produced in dense cultures, perhaps a LOX-derived metabolite, activates conidium formation, while a factor(s) produced in low-density cultures stimulates sclerotium formation. Copyright © 2008, American Society for Microbiology. All Rights Reserved.
Note:
Related Files :
biosynthesis
Genetics
Growth, Development and Aging
metabolism
molecular genetics
phenotype
quorum sensing
עוד תגיות
תוכן קשור
More details
DOI :
10.1128/AEM.00565-08
Article number:
Affiliations:
Database:
סקופוס
Publication Type:
מאמר
;
.
Language:
אנגלית
Editors' remarks:
ID:
30417
Last updated date:
02/03/2022 17:27
Creation date:
17/04/2018 00:54
You may also be interested in
Scientific Publication
Morphological transitions governed by density dependence and lipoxygenase activity in Aspergillus flavus
74
Horowitz Brown, S., Department of Plant Pathology, University of Wisconsin - Madison, Madison, WI 53706-1598, United States
Zarnowski, R., Department of Medical Microbiology and Immunology, University of Wisconsin - Madison, 1550 Linden Dr., Madison, WI 53706-1598, United States
Sharpee, W.C., Department of Plant Pathology, University of Wisconsin - Madison, Madison, WI 53706-1598, United States
Keller, N.P., Department of Plant Pathology, University of Wisconsin - Madison, Madison, WI 53706-1598, United States, Department of Medical Microbiology and Immunology, University of Wisconsin - Madison, 1550 Linden Dr., Madison, WI 53706-1598, United States, 3476 Microbial Science Building, Department of Medical Microbiology and Immunology, UW - Madison, 1550 Linden Dr., Madison, WI 53706, United States
Morphological transitions governed by density dependence and lipoxygenase activity in Aspergillus flavus
Aspergillus flavus differentiates to produce asexual dispersing spores (conidia) or overwintering survival structures called sclerotia. Results described here show that these two processes are oppositely regulated by density-dependent mechanisms and that increasing the cell density (from 10 1 to 107 cells/plate) results in the lowest numbers of sclerotial and the highest numbers of conidial. Extract from spent medium of low-cell-density cultures induced a high-sclerotium-number phenotype, whereas high-cell-density extract increased conidiation. Density-dependent development is also modified by changes in lipid availability. Exogenous linoleic acid increased sclerotial production at intermediate cell densities (104 and 105 cells/plate), whereas oleic and linolenic acids inhibited sclerotium formation. Deletion of Aflox encoding a lipoxygenase (LOX) greatly diminished density-dependent development of both sclerotia and conidia, resulting in an overall increase in the number of sclerotia and a decrease in the number of conidia at high cell densities (>105 cells/plate). Aflox mutants showed decreased linoleic acid LOX activity. Taken together, these results suggest that there is a quorum-sensing mechanism in which a factor(s) produced in dense cultures, perhaps a LOX-derived metabolite, activates conidium formation, while a factor(s) produced in low-density cultures stimulates sclerotium formation. Copyright © 2008, American Society for Microbiology. All Rights Reserved.
Scientific Publication
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