leading to the formation of 7-hydroxyheptanal (F), acetic acid (G) and benzoic acid (I). Again, a larger molecule remains (J). F, G and I can undergo Schmidt reaction, if not degraded via acidic degradation by alcohol dehydrogenase (ADH) to methylamine and carbon dioxide (H). 7-hydroxyheptane is oxidized to 3-methylheptanedioic acid (K). Further metabolism leads to the formation of several smaller organic molecules such as amines (M), carbon dioxide (N) and acetic acid (O). The latter is again metabolized by ADH to methylamine and carbon dioxide (Q). Molecule J is cleaved into a number of small compounds such as acetic acid (L), methylamine and carbon dioxide (P), and a series of small methylated compounds. Efficacy and adverse effects Interactions When adding cytochalasin B and the beta-andrenergic agonist (-)-isoproterenol, prostaglandin E1 or cholera toxin to wild type S49 lymphoma cells, cAMP accumulates. Cytochalasin B is unable to transform 3T3-like tumor cells, but it did increase the frequency of cell transformation by the polyoma virus 8-40 fold. Furthermore, CB can intensify pinocytosis, which is induced by concanavalin A in amoeba proteus. Cytochalasin B can also interact with the auxin indole-3-acetic acid which occurs in wheat coleoptile segments and maize roots. This interaction leads to the inhibition of vesicle transport and secretion of cell wall components and thereby blocks elongation and growth. Efficacy In vitro studies showed that a concentration of 30 μM of cytochalasin B significantly reduces the relative viscosity of a 20 μM normal actin filament solution as well as it has decreased in a 20 μMm gluthathionyl-actin filament solution. In vivo the effective concentration is even lower. It seemed that a 2 μM concentration is sufficient in living cells to accomplish a measurable influence on the actin polymerization. The nucleation phase took 2-4 times as long as in the control groups. On elongation, the effects were minimal; on annealing negligible. This might be due to an actual difference in molecular interactions of cytochalasin B during those three steps or simply due to the fact that the lag phase is the rate-determining step in the overall polymerization. Applications Actin polymerization studies As cytochalasin B inhibits actin filament polymerization, many cellular processes depending on actin filament functions are affected. Cytokinesis is inhibited, however, mitosis is unaffected. Due to the effects on several cellular functions but lack of general toxicity, cytochalasin B is applied in actin polymerization studies, cell imaging methods, cell cycle studies