It induces chlorosis in germinating seedlings of many dicotyledonous plants. Tentoxin has been postulated to inhibit cyclic photophosphorylation by acting as an energy transfer inhibitor at the terminal steps of ATP synthesis and to target the F1 moiety of photosynthetic H+-ATPases. A kinetic analysis of the action of tentoxin on the chloroplast F1 H+-ATPase (CF1) portion of chloroplast ATP synthase has been reported.
Tentoxin is phytotoxic, which induces chlorosis in plant leaves and germinating seedlings. It also halts photophosphorylation by inhibiting chloroplastic ATP synthase. Tentoxin over energizes thylakoids and is converted to isotentoxin by UV irradiation.
General description
Tentoxin is a majorly occurring cyclic tetrapeptide mycotoxin that is excreted by the Alternaria fungal species like Alternaria alternata and Alternaria tenuis.