Which of the following amino acids is involved in one carbon pool?

Ans. is 'a' i.e., Glycine* Goups, containing a single carbon atom are called one carbon groups. One carbon groups are formed from following amino acids during their metabolism:- Serine, glycine, histidine and tryptophan. One carbon groups formed during metabolism are: methyl (CH3), methylene (CH2), methenyl (C H), formyl (CHO) and formimino (CH=NH)* These one carbon groups are transferred by way of tetrahydrofolate (THF), which is derivative of folic acid. One carbon groups carried by THF are attached either to nitrogen N5 or N10 or to both N5 and N10. Different one corbon derivatives of THF are- N5- methyl THF, N5, N10-methylene THF, N5, N10-methenyl THF, N5- formyl THF and N5-formimino THF. These derivatives are interconvertable.