Binding studies of a putative C. pseudotuberculosis target protein from Vitamin B12 Metabolism

Methylations in vitamin B12 biosynthesis and catalysis

Vitamin B₁₂ is an essential biomolecule that assists in the catalysis of methyl transfer and radical-based reactions in cellular metabolism. The structure of B₁₂ is characterized by a tetrapyrrolic corrin ring with a central cobalt ion coordinated with an upper ligand, and a lower ligand anchored via a nucleotide loop. Multiple methyl groups decorate B₁₂, and their presence (or absence) have structural and functional consequences. In this minireview, we focus on the methyl groups that distinguish vitamin B₁₂ from other tetrapyrrolic biomolecules and from its own naturally occurring analogues called cobamides. We draw information from recent advances in the field to understand the origins of these methyl groups and the enzymes that incorporate them, and discuss their biological significance.

Effect of different dosage of sodium butyrate and niacin on growth, fecal microbiota and vitamin B metabolism in weaned piglets

AIMS

Our study aimed to evaluate the effects of different dosages of sodium butyrate and niacin on the growth performance, fecal vitamin B and microbiota in weaned piglets.

METHODS AND RESULTS

Seventy-two weaned piglets (Duroc×Landrace×Yorkshire, age of 21d) were randomly assigned to 1 of 6 treatments (12 pigs / treatment): the control (CT) group was administered a basal diet. The groups which concentration ratio of sodium butyrate to niacin were 100: 1, 100: 2, 100: 4, 100: 8 and 100: 16 (BN1, BN2, BN4, BN8, BN16) were administered a basal diet supplemented with 2000 mg·kg^-1 sodium butyrate and 20 mg·kg^-1 , 40 mg·kg^-1 , 80 mg·kg^-1 , 160 mg·kg^-1 or 320 mg·kg^-1 niacin. After 14-d treatment, the samples were collected. The results showed that feed conversion rate (FCR) was reduced and average daily gain (ADG) was increased in BN2 (P < 0.05). The diarrhea index of pigs decreased with the low supplement. Additionally, compared with CT group, other groups significantly increased (P < 0.05) the abundance of Firmicutes (BN4, phylum), Lactobacillaceae (BN8, family), Megasphaera (BN8, genus), and Lactobacillus (BN8, genus). Furthermore, the sodium butyrate and niacin supplementation influence vitamin B1, vitamin B2, pyridoxine, niacin, nicotinamide, and vitamin B12 (P < 0.05). Correlation analysis of the association of microorganisms with vitamin B indicated that changes of vitamin B metabolism have potential correlation with alterations of fecal microbiota in weaned piglets.

CONCLUSIONS

The results indicated that adding of sodium butyrate and niacin in the diet could promote the performance and improve the fecal microbiota and vitamin B metabolism in weaned piglets.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our study might provide clues to the research of correlations between fecal bacteria and fecal vitamin B, and these findings will contribute to the direction of future research in weaned piglets.

Conformational dynamics of myoglobin in the presence of vitamin B12: A spectroscopic and in silico investigation

Myoglobin is an essential transport protein of heart and muscle tissues that acts as a local oxygen reservoir and a marker in different diseased conditions. On the other hand, Vitamin B12 is a vital nutrient that helps synthesize red blood cells, DNA, and proteins. To understand the ability of vitamin B12 to bind to the excess of myoglobin produced in the body under certain conditions (muscle injuries, severe trauma, etc.), it is essential to dig into the interaction between them. Therefore, the present study reports the binding interaction of vitamin B12 and myoglobin employing different spectroscopic and computational methods. The myoglobin's intrinsic fluorescence is quenched by vitamin B12 via static nature as observed from steady-state as well as time-resolved fluorescence measurements. The microenvironment of myoglobin's tryptophan residue gets affected, but there is no change observed in its α-helical content by vitamin B12 as seen from synchronous fluorescence and circular dichroism measurements. The probable binding of vitamin B12 on myoglobin was elucidated through molecular docking, and the interaction stability was studied by molecular dynamics simulation. The determination of vitamin B12's affinity to myoglobin and its effect on the conformational transitions of myoglobin might afford valuable insight for clinical pharmacology.

100 Years of Suramin

Suramin is 100 years old and is still being used to treat the first stage of acute human sleeping sickness, caused by Trypanosoma brucei rhodesiense Suramin is a multifunctional molecule with a wide array of potential applications, from parasitic and viral diseases to cancer, snakebite, and autism. Suramin is also an enigmatic molecule: What are its targets? How does it get into cells in the first place? Here, we provide an overview of the many different candidate targets of suramin and discuss its modes of action and routes of cellular uptake. We reason that, once the polypharmacology of suramin is understood at the molecular level, new, more specific, and less toxic molecules can be identified for the numerous potential applications of suramin.