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One of a series of structurally related fungal metabolic products which, among other effects on biological systems, selectively and reversibly block cytokinesis while not affecting karyokinesis; the molecule with minor variations consists of a benzyl-substituted hydroaromatic isoindolone system, which in turn is fused to a small macrolide-like cyclic ring.



one of a group of related antibiotics produced by certain types of Fungi Imperfecti. Cytochalasins were isolated in 1967 by a British research group (S. B. Carter and coworkers). The cytochalasins that have been identified— designated A, B, C, D, E, and F—have the structural formula

and are differentiated by the side groups R1 and R2, representing different radicals.

Cytochalasins are crystal compounds with a molecular weight of 477 to 507 and a melting point of 182° to 270°C; they are insoluble in water but freely soluble in organic solvents. In a low concentration of 1 microgram per milliliter (μg/ml), cytochalasins inhibit the formation of an intracellular dividing membrane after the complete separation of the chromosomes that takes place in cell division, or mitosis, and thus lead to the formation of multinucleate cells. In concentrations of 10 μg/ml, cytochalasins cause the nucleus to be drawn out of the cell (enucleation). Another effect of cytochalasins is to block endocytosis in macrophages. The action of cytochalasins is reversible: upon their removal, endocytosis is reestablished; the nucleus, which having left the cell has remained connected to it by a cytoplasmic bridge, reenters the cell. Cytochalasins are believed to affect the microfilaments that are elements of the cell contraction system. Cytochalasins are used in research work in cytology and physiology.


Carter, S. B. “Effects of Cytochalasins on Mammalian Cells.” Nature, 1967, vol. 213, no. 5073.
Carter, S. B. “The Cytochalasins as Research Tools in Cytology.” Endeavour, 1972, vol. 31, no. 113.


References in periodicals archive ?
The cytochalasins are a group of toxic fungal metabolites which show marked cytotoxic effects on mammalian cells in tissue culture.
arcuata which is reported in this paper produced an intimate mixture of four cytochalasins.
1]H NMR was used to monitor the separation of the mixture of cytochalasins in the eluent.
Four cytochalasins, termed phomachalasins A-D (11-14), were isolated and characterised as three closely related 26- oxa[16] and one new[15] cytochalasan.
The cytochalasins are a group of toxic fungal metabolites which exhibited a broad spectrum of biological activity including antibiotic and antitumor activity (Katagiri and Matsura 1971), inhibition of HIV-1 protease (Wells et al.
In addition, isolation of cytochalasin J, dechlorogriseofulvin, griseofulvin, demethylharzianicacid, harzianic acid and 2-hexylidene-3methyl-succinic acid from the present study shows that plants from Malaysia rainforest could be hosts to a great diversity of endophytic fungi that serve as a remarkable source of bioactive compounds.
Toxicity and plant growth regulator effects of cytochalasin H isolated from Phomopsis sp.
The company also has patents relating to the biological stenting of traumatized blood vessels by administration of cytoskeletal inhibitors such as cytochalasins (Biostent(R) therapy).
Apoptosis induction in HCT116 cells by cytochalasins isolated from the fungus Daldinia vernicosa.