Essential Nutrients: Folate, B12 and 1-Carbon Metabolism
Channel: Liam Skoda
Date: 04/04/2023

This is an extract from a longer upcoming video on essential nutrients, it will be the start of a series of videos on nutrition from a medical/critical care perspective.

This video focuses on the biochemistry of vitamins B9 (folate) and B12 (cobalamin), the multiple tetrahydrofolate cycles and the methionine/homocysteine cycle. It will also briefly discuss the effects of B9 and B12 deficiency and drugs such as nitrous oxide, methotrexate and 5-fluorouracil. Presentation is my own work. Content developed during preparation for CICM primary exam. 

Chapters:
00:00:00 Folate structure and activation.
00:01:47 N-10 Formyl Tetrahydrofolate and purine synthesis.
00:03:40 Methanyl, methylene, serine and glycine.
00:04:40 Thymidylate synthase.
00:05:25 N5 methyl tetrahydrofolate and vitamin B12.
00:06:45 Methionine synthase and S-adenosyl methionine.
00:08:15 Completion of the methionine cycle.
00:08:51 Choline, betaine and sarcosine.
00:09:58 Propionyl CoA and methylmalonyl CoA mutase.
00:11:30 Vitamin B12 deficiency.
00:13:10 Nitrous oxide.
00:15:10 Folate deficiency and methotrexate.
00:17:54 5-fluorouracil.
00:18:30 End.

Major references include Mark's Basic Medical Biochemistry, the youtube channel @CatalystUniversity and various journal articles. You can also check out my previous video for background on redox reactions, the citric acid cycle, fatty acid and amino acid metabolism. ETA for the full essential nutrients video will be 1-2 weeks from now.