<Tr> <Td> </Td> <Td> This article needs more medical references for verification or relies too heavily on primary sources . Please review the contents of the article and add the appropriate references if you can . Unsourced or poorly sourced material may be challenged and removed . (October 2016) </Td> <Td> </Td> </Tr> <P> Several forms (vitamers) of vitamin B are known: </P> <Ul> <Li> Pyridoxine (PN), the form most commonly given as vitamin B supplement </Li> <Li> Pyridoxine 5 ′ - phosphate (P5P) </Li> <Li> Pyridoxal (PL) </Li> <Li> Pyridoxal 5 ′ - phosphate (PLP), the metabolically active form (sold as P - 5 - P vitamin supplement) </Li> <Li> Pyridoxamine (PM) </Li> <Li> Pyridoxamine 5 ′ - phosphate (PMP) </Li> <Li> 4 - Pyridoxic acid (PA), the catabolite which is excreted in urine </Li> <Li> Pyritinol, a semi-synthetic derivative of pyridoxine, where two pyridoxine moieties are bound by a disulfide bridge . </Li> </Ul> <Li> Pyridoxine (PN), the form most commonly given as vitamin B supplement </Li>

In which of the following functions does vitamin b6 play a key role