Many microbial producers of coenzyme B12 family cofactors together with their metabolically interdependent pathways are comprehensively studied and successfully used both in natural ecosystems dominated by auxotrophs, including bacteria and mammals, and in the safe industrial production of vitamin B12. Metabolic reconstruction for genomic and metagenomic data and functional genomics continue to mine the microbial and genetic resources for biosynthesis of the vital vitamin B12. Availability of metabolic engineering techniques and usage of affordable and renewable sources allowed improving bioprocess of vitamins, providing a positive impact on both economics and environment. The commercial production of vitamin B12 is mainly achieved through the use of the two major industrial strains, Propionobacterium shermanii and Pseudomonas denitrificans, that involves about 30 enzymatic steps in the biosynthesis of cobalamin and completely replaces chemical synthesis. However, there are still unresolved issues in cobalamin biosynthesis that need to be elucidated for future bioprocess improvements. In the present work, we review the current state of development and challenges for cobalamin (vitamin B12) biosynthesis, describing the major and novel prospective strains, and the studies of environmental factors and genetic tools effecting on the fermentation process are reported.

Background: The endogenous ecto-enzyme and exogenously administered alkaline phosphatase (ALP) have been evidenced to significantly attenuate inflammatory conditions, including Toll-like receptor 4 (TLR4)-related signaling and cytokine overexpression, barrier tissue dysfunction and oxidative stress, and metabolic syndrome and insulin resistance, in experimental models of colitis, liver failure, and renal and cardiac ischemia-reperfusion injury. This suggests multiple mechanisms of ALP anti-inflammatory action that remain to be fully elucidated. Methods: Recent studies have contributed to a deeper comprehension of the role played by ALP in immune metabolism. This review outlines the established effects of ALP on lipopolysaccharide (LPS)-induced inflammation, including the neutralization of LPS and the modulation of purinergic signaling. Results: The additional mechanisms of anti-inflammatory activity of ALP observed in different pathologies are proposed. Conclusions: The anti-inflammatory pathways of ALP may include a scavenger receptor (CD36)-mediated activation of β-oxidation and oxidative phosphorylation, caveolin-dependent endocytosis, and selective autophagy-dependent degradation.

The global increase in population has placed significant pressure on food security, leading to the emergence of aquaculture as a vital source of aquatic foods. However, rising costs and limited fish meal availability in aquafeeds have driven the search for alternative protein sources. While plant-based ingredients have been integrated into commercial aquafeeds, they come with challenges such as low protein content, palatability issues, and the presence of antinutritional factors. In this context, fish silage, made from fish waste and discarded fish, stands out as a promising alternative technology due to its cost-effectiveness and sustainability attributes. The production of fish silage involves the addition of organic/inorganic acids or lactic acid bacteria to homogenized fish waste, yielding a valuable mixture rich in peptides and free amino acids, offering significant nutritional benefits for animal diets. This review aims to promote sustainable practices in the aquaculture industry by analyzing research results related to ensiling technology, appraising the advantages and disadvantages of using fish silage as a feed ingredient, and focusing on emerging trends in this field.

A novel extracellular alkaline phosphatase/phosphodiesterase from the structural protein family PhoD that encoded by the genome sequence of the marine bacterium Cobetia amphilecti KMM 296 (CamPhoD) has been expressed in Escherichia coli cells. The calculated molecular weight, the number of amino acids, and the isoelectric point (pI) of the mature protein’s subunit are equal to 54832.98 Da, 492, and 5.08, respectively. The salt-tolerant, bimetal-dependent enzyme CamPhoD has a molecular weight of approximately 110 kDa in its native state. CamPhoD is activated by Co²⁺, Mg²⁺, Ca²⁺, or Fe³⁺ at a concentration of 2 mM and exhibits maximum activity in the presence of both Co²⁺ and Fe³⁺ ions in the incubation medium at pH 9.2. The exogenous ions, such as Zn²⁺, Cu²⁺, and Mn²⁺, as well as chelating agents EDTA and EGTA, do not have an appreciable effect on the CamPhoD activity. The temperature optimum for the CamPhoD activity is 45 °C. The enzyme catalyzes the cleavage of phosphate mono- and diester bonds in nucleotides, releasing inorganic phosphorus from p-nitrophenyl phosphate (pNPP) and guanosine 5′-triphosphate (GTP), as determined by the Chen method, with rate approximately 150- and 250-fold higher than those of bis-pNPP and 5′-pNP-TMP, respectively. The Michaelis–Menten constant (K_m), V_max, and efficiency (k_cat/K_m) of CamPhoD were 4.2 mM, 0.203 mM/min, and 7988.6 S⁻¹/mM; and 6.71 mM, 0.023 mM/min, and 1133.0 S⁻¹/mM for pNPP and bis-pNPP as the chromogenic substrates, respectively. Among the 3D structures currently available, in this study we found only the low identical structure of the Bacillus subtilis enzyme as a homologous template for modeling CamPhoD, with a new architecture of the phosphatase active site containing Fe³⁺ and two Ca²⁺ ions. It is evident that the marine bacterial phosphatase/phosphidiesterase CamPhoD is a new structural member of the PhoD family.

Desirable changes in the biochemical composition of food plants is a key outcome of breeding strategies. The subsequent localization of nutritional phytochemicals in plant tissues gives important information regarding the extent of their synthesis across a tissue. We performed a detailed metabolomic analysis of phytochemical substances of grains from Zea mays L. (var. Pioneer) by tandem mass spectrometry and localization by confocal microscopy. We found that anthocyanins are located mainly in the aleurone layer of the grain. High-performance liquid chromatography in combination with ion trap tandem mass spectrometry revealed the presence of 56 compounds, including 30 polyphenols. This method allows for effective and rapid analysis of anthocyanins by plotting their distribution in seeds and grains of different plants. This approach will permit a more efficient screening of phenotypic varieties during food plant breeding.

A novel wild-type recombinant cold-active α-d-galactosidase (α-PsGal) from the cold-adapted marine bacterium Pseudoalteromonas sp. KMM 701, and its mutants D451A and C494N, were studied in terms of their structural, physicochemical, and catalytic properties. Homology models of the three-dimensional α-PsGal structure, its active center, and complexes with D-galactose were constructed for identification of functionally important amino acid residues in the active site of the enzyme, using the crystal structure of the α-galactosidase from Lactobacillus acidophilus as a template. The circular dichroism spectra of the wild α-PsGal and mutant C494N were approximately identical. The C494N mutation decreased the efficiency of retaining the affinity of the enzyme to standard p-nitrophenyl-α-galactopiranoside (pNP-α-Gal). Thin-layer chromatography, matrix-assisted laser desorption/ionization mass spectrometry, and nuclear magnetic resonance spectroscopy methods were used to identify transglycosylation products in reaction mixtures. α-PsGal possessed a narrow acceptor specificity. Fructose, xylose, fucose, and glucose were inactive as acceptors in the transglycosylation reaction. α-PsGal synthesized -α(1→6)- and -α(1→4)-linked galactobiosides from melibiose as well as -α(1→6)- and -α(1→3)-linked p-nitrophenyl-digalactosides (Gal₂-pNP) from pNP-α-Gal. The D451A mutation in the active center completely inactivated the enzyme. However, the substitution of C494N discontinued the Gal-α(1→3)-Gal-pNP synthesis and increased the Gal-α(1→4)-Gal yield compared to Gal-α(1→6)-Gal-pNP.