glucuronoxylan D-glucuronate + n S-adenosyl-L-methionine => glucuronoxylan 4-O-methyl-D-glucuronate + n S-adenosyl-L-homocysteine + n H(+)
glucuronoxylan d-glucuronate + n s-adenosyl-l-methionine => glucuronoxylan 4-o-methyl-d-glucuronate + n s-adenosyl-l-homocysteine + n h(+)
glucuronoxylan D-glucuronate + n S-adenosyl-L-methionine => glucuronoxylan 4-O-methyl-D-glucuronate + n S-adenosyl-L-homocysteine + n H(+)
glucuronoxylan d-glucuronate + n s-adenosyl-l-methionine => glucuronoxylan 4-o-methyl-d-glucuronate + n s-adenosyl-l-homocysteine + n h(+)