EFFECT OF AN ANTISENSE PECTIN METHYLESTERASE GENE ON THE CHEMISTRY OFPECTIN IN TOMATO (LYCOPERSICON-ESCULENTUM) JUICE

Pectins in tomato (Lycopersicon esculentum) juice processed from trans genic fruits with reduced levels of pectin methylesterase activity and from control fruits were characterized for total uronic acid, degree of methoxylation (DOM), and molecular mass. The molecular weights of p ectins isolated from transgenic fruit juice are much higher than the m olecular weights of pectins isolated from control fruit juice under al l processing conditions. Depending on processing conditions, juice fro m transgenic fruits contained 30-50% higher amounts of total uronic ac ids and had 25-250% higher DOM compared to juice from control fruits.