There seems to be a complex relationship between vitamin B12 and photosynthesis (prokaryotic and eukaryotic), but it is hard to pinpoint its meaning.
- On the one hand, the pathways leading to key photosynthetic pigments, including chlorophyll and bacteriochlorophyll, and vitamin B12 share precursors. This suggests competition between these pathways, to either use the precursors to synthesize the pigments, or channel them to vitamin B12.
- On the other hand, articles show that vitamin B12 is needed for photosynthesis, as this process can be limited by the availability of vitamin B12 when auxotrophies exist. So, it is not a simple competition for precursors, right? Are some photosynthesis-related enzymes vitamin B12 dependent?
- To complicate matters further, vitamin B12 regulates gene expression of genes related to photosynthesis, and of course, there is its role as co-factor of many enzymes.
Can some please help me understand the link between vitamin B12 and photosynthesis. Are there key enzymes involved in the synthesis of photosynthetic pigments vitamin B12-dependent?
Are there other photosynthesis-related proteins vitamin B12-dependent?
The literature I have found is focused on fine details (biochemical or physiological) on the relation between vitamin B12 and photosynthesis. Are there any articles where I can read about the big-picture of what is known about this relationship?
Thanks
Kindly check this link
https://grantome.com/grant/NIH/R00-GM083343-04
Thank you very much Chinaza Godswill Awuchi. The paper was very useful. In short, from what I have learned:
1. The link is only indirect, and is present when vitamin B12 is needed as a co-factor for other enzymes.
2. Only a few groups of bacteria and archaea can synthesize it.
3. Some organisms, like cyanobacteria, utilize a variant, called pseudocobalamin.
Vitamin B12 (cobalamin), the antipernicious anemia factor, is unique among the vitamins in that its synthesis is restricted to the prokaryotic world. In fact, cobalamin is made along one of two related biosynthetic pathways, which differ in their timing of cobalt insertion and requirement for molecular oxygen. The purple bacteria appear to utilize, exclusively, the pathway requiring oxygen (aerobic route). In this chapter, the aerobic pathway for cobalamin biosynthesis is described. The biosynthetic pathway for cobalamin is shared, in part, with that for other modified tetrapyrroles such as heme, bacteriochlorophyll and siroheme. Cobalamin biosynthesis diverges from heme and chorophyll at uroporphyrinogen III, the first macrocyclic intermediate of the pathway. The transformation of uroporphyrinogen III into cobalamin requires the addition of eight S-adenosyl-L-methionine derived methyl groups, ring contraction, decarboxylation, amidation, cobalt insertion, adenosylation and the attachment of a lower nucleotide loop that houses an unusual base in the form of dimethylbenzimidazole. In total, around thirty enzymes are required for the complete de novo biosynthesis of the coenzyme form of cobalamin, a coenzyme that appears to be required for a number of cellular activities in the purple bacteria including the formation of the active photosynthetic apparatus.
Oh, I see Devidas Bhagat . There is a direct link. Thanks a lot!
Article Vitamin B12 in photosynthetic bacteria and methionine synthe...
http://jb.asm.org/content/177/15/4481.full.pdf
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