Alterations in superoxide dismutase, glutathione, and peroxides in the plasmodial slime mold Physarum polycephalum during differentiation

✍ Scribed by R. G. Allen; R. K. Newton; R. S. Sohal; G. L. Shipley; C. Nations

• Publisher: John Wiley and Sons
• Year: 1985
• Tongue: English
• Weight: 692 KB
• Volume: 125
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.1041250308

✦ Synopsis

Changes in the level of antioxidant defenses and the concentration of free radical by-products were examined in differentiating (M3cVII and LU897 x LU863), non-differentiating (LU887 x LU897), and heterokaryon microplasmodia of the slime mold Physarum polycephalum during spherulation in salts-only medium. As differentiation proceeded, superoxide dismutase activity increased by as much as 46 fold; glutathione concentration and t h e rate of oxygen consumption decreased; cyanide-resistant respiration, hydrogen peroxide, and organic peroxide concentrations increased. The non-differentiating culture failed to exhibit any of these changes. A heterokaryon obtained by the fusion of differentiating and non-differentiating strains was observed to differentiate at a very retarded rate and to exhibit t h e changes observed in the spherulating strains at a correspondingly slower rate. These observations suggest that a free radical mechanism may be involved in the differentiation of Physarum microplasmodia into spherules.