The structure and synthesis of malformin A

Area of Science:

• Biochemistry
• Plant Science
• Organic Chemistry

Background:

• Malformin A is a cyclic peptide phytotoxin known to induce characteristic curvatures in plant roots.
• Previous structural proposals for malformin A existed but required re-evaluation.

Purpose of the Study:

• To re-examine and definitively establish the correct chemical structure of malformin A.
• To synthesize the proposed structure and verify its identity and biological activity.

Main Methods:

• Chemical degradation analysis of malformin A.
• Synthesis of a novel cyclic peptide structure.
• Biological assays using corn root growth.

Main Results:

• A revised structure, cyclo(D-Cys-D-Cys-L-Val-D-Leu-L-Ile) disulfide, was established for malformin A.
• The synthesized compound was identical to natural malformin A.
• The synthetic malformin A induced significant corn root curvatures at 0.1 µg/ml.

Conclusions:

• The established structure represents the correct chemical identity of malformin A.
• The synthetic compound serves as a reliable standard for malformin A research.
• Malformin A's phytotoxicity is confirmed with a precise structural determination.