-
Cellular and Molecular Gastroenterology... 2020Biotin is a water-soluble vitamin that is indispensable for human health. Biotin deficiency can cause failure-to-thrive, immunodeficiency, alopecia, dermatitis, and...
BACKGROUND & AIMS
Biotin is a water-soluble vitamin that is indispensable for human health. Biotin deficiency can cause failure-to-thrive, immunodeficiency, alopecia, dermatitis, and conjunctivitis. We previously reported that biotin deficiency also can lead to severe colitis in mice, which is completely reversed with supplementation. Our aim in this study was to determine if high-dose biotin supplementation can provide a therapeutic benefit in a preclinical model for inflammatory bowel disease (IBD) and to identify the molecular mechanism by which this occurs.
METHODS
Mice were challenged with dextran sodium sulfate to induce colitis and were treated with 1 mmol/L biotin to induce or maintain remission. Clinical response was monitored by the Disease Activity Index and fecal calprotectin levels. The colon tissue was investigated for histology, length, as well as expression of inflammatory cytokines (interleukin 6, tumor necrosis factor-α, interleukin 1β), intestinal permeability, tight junctions (zonula occludens-1 and claudin-2), and the transcription factor nuclear factor-κB (NF-κB).
RESULTS
Biotin therapy led to delayed onset and severity of colitis as well as accelerated healing. There was improvement in the Disease Activity Index, fecal calprotectin levels, colon length, and histology. In addition, biotin-treated mice had reduced expression of inflammatory cytokines, reduced intestinal permeability, and reduced activation of NF-κB.
CONCLUSIONS
Oral supplementation with biotin provides benefit for maintenance and induction of remission in the dextran sodium sulfate preclinical model for IBD. Biotin does this by reducing the activation of NF-κB, which prevents the production of inflammatory cytokines and helps maintain the integrity of the intestinal barrier. Clinically, the NF-κB pathway is important in the development of IBD and this finding suggests that biotin may have therapeutic potential for patients with IBD.
Topics: Animals; Biotin; Colitis; Dextran Sulfate; Dietary Supplements; Humans; Kruppel-Like Transcription Factors; Mice; Mice, Inbred C57BL; NF-kappa B; Regeneration; Signal Transduction; Stem Cells
PubMed: 31786364
DOI: 10.1016/j.jcmgh.2019.11.011 -
Journal of Nanobiotechnology Mar 2014The interaction between biotin and avidin is utilized in a wide range of assay and diagnostic systems. A robust material capable of binding biotin should offer scope in...
BACKGROUND
The interaction between biotin and avidin is utilized in a wide range of assay and diagnostic systems. A robust material capable of binding biotin should offer scope in the development of reusable assay materials and biosensor recognition elements.
RESULTS
Biotin-selective thin (3-5 nm) films have been fabricated on hexadecanethiol self assembled monolayer (SAM) coated Au/quartz resonators. The films were prepared based upon a molecular imprinting strategy where N,N'-methylenebisacrylamide and 2-acrylamido-2-methylpropanesulfonic acid were copolymerized and grafted to the SAM-coated surface in the presence of biotin methyl ester using photoinitiation with physisorbed benzophenone. The biotinyl moiety selectivity of the resonators efficiently differentiated biotinylated peptidic or carbohydrate structures from their native counterparts.
CONCLUSIONS
Molecularly imprinted ultra thin films can be used for the selective recognition of biotinylated structures in a quartz crystal microbalance sensing platform. These films are stable for periods of at least a month. This strategy should prove of interest for use in other sensing and assay systems.
Topics: Acrylamides; Benzophenones; Biosensing Techniques; Biotin; Biotinylation; Carbohydrates; Molecular Imprinting; Nanostructures; Peptides; Quartz Crystal Microbalance Techniques
PubMed: 24655809
DOI: 10.1186/1477-3155-12-8 -
The ISME Journal Nov 2022Biotin (vitamin B) is involved in a wide range of essential biochemical reactions and a crucial micronutrient that is vital for many pro- and eukaryotic organisms. The...
Biotin (vitamin B) is involved in a wide range of essential biochemical reactions and a crucial micronutrient that is vital for many pro- and eukaryotic organisms. The few biotin measurements in the world's oceans show that availability is subject to strong fluctuations. Numerous marine microorganisms exhibit biotin auxotrophy and therefore rely on supply by other organisms. Desthiobiotin is the primary precursor of biotin and has recently been detected at concentrations similar to biotin in seawater. The last enzymatic reaction in the biotin biosynthetic pathway converts desthiobiotin to biotin via the biotin synthase (BioB). The role of desthiobiotin as a precursor of biotin synthesis in microbial systems, however, is largely unknown. Here we demonstrate experimentally that bacteria can overcome biotin auxotrophy if they retain the bioB gene and desthiobiotin is available. A genomic search of 1068 bacteria predicts that the biotin biosynthetic potential varies greatly among different phylogenetic groups and that 20% encode solely bioB and thus can potentially overcome biotin auxotrophy. Many Actino- and Alphaproteobacteria cannot synthesize biotin de novo, but some possess solely bioB, whereas the vast majority of Gammaproteobacteria and Flavobacteriia exhibit the last four crucial biotin synthesis genes. We detected high intra- and extracellular concentrations of the precursor relative to biotin in the prototrophic bacterium, Vibrio campbellii, with extracellular desthiobiotin reaching up to 1.09 ± 0.15*10 molecules per cell during exponential growth. Our results provide evidence for the ecological role of desthiobiotin as an escape route to overcome biotin auxotrophy for bacteria in the ocean and presumably in other ecosystems.
Topics: Bacteria; Biotin; Ecosystem; Micronutrients; Phylogeny; Vitamins
PubMed: 35963899
DOI: 10.1038/s41396-022-01304-w -
The American Journal of Clinical... Nov 2008Biotin is likely transported into cerebral spinal fluid (CSF) via one or more specific transporters. Concentrations of biotin in CSF measured by using modern analytic...
BACKGROUND
Biotin is likely transported into cerebral spinal fluid (CSF) via one or more specific transporters. Concentrations of biotin in CSF measured by using modern analytic techniques that are specific for biotin and biotin metabolites have not previously been reported.
OBJECTIVES
We aimed to accurately measure the concentration of biotin and major biotin metabolites, biotin sulfoxide (BSO) and bisnorbiotin (BNB), in the CSF of children.
DESIGN
Concentrations of biotin were determined initially as total avidin-binding substances (TABS) in CSF obtained by lumbar puncture from 55 children. Biotin, BSO, and BNB were quantitated by HPLC and an avidin-binding assay in CSF samples from a subset of 11 children.
RESULTS
Concentrations of TABS in CSF averaged 1.6 nmol/L with substantial variability (SD = 1.3 nmol/L). CSF concentrations of biotin and biotin analogs varied widely, but substantial amounts of BSO were detected in every sample. Biotin accounted for 42 +/- 16%, BSO for 41 +/- 12%, and BNB for 8 +/- 14% of the total. It was surprising that the molar sum of biotin, BSO, and BNB on average was >200-fold the TABS concentrations from the same CSF sample. Using several analytic approaches, we found no masking of detection, nor did we find degradation of biotin or BSO. Gel electrophoresis and streptavidin Western blot detected several biotinylated proteins in CSF.
CONCLUSIONS
Biotin appears to be bound to protein covalently, reversibly, or both, and this binding likely accounts for the increase in detectable biotin after HPLC. Protein-bound biotin may play an important role in biotin nutriture of the brain.
Topics: Adolescent; Avidin; Binding, Competitive; Biotin; Cerebrospinal Fluid; Child; Child, Preschool; Chromatography, High Pressure Liquid; Female; Humans; Infant; Male
PubMed: 18996865
DOI: 10.3945/ajcn.2008.26525 -
Current Protocols Mar 2023Proteins frequently function in high-order complexes. Defining protein-protein interactions is essential to acquiring a full understanding of their activity and...
Proteins frequently function in high-order complexes. Defining protein-protein interactions is essential to acquiring a full understanding of their activity and regulation. Proximity biotinylation has emerged as a highly specific approach to capture transient and stable interactions in living cells or organisms. Proximity biotinylation exploits promiscuous biotinylating enzymes fused to a bait protein, resulting in the biotinylation of adjacent endogenous proteins. Biotinylated interactors are purified under very strict conditions and identified by mass spectrometry to obtain a high-confidence list of candidate binding partners. AirID is a recently described biotin ligase specifically engineered for proximity labeling. This protocol details proximity biotinylation by AirID, using protein complexes that form during a type I interferon response as an example. It covers the construction and validation of AirID fusion proteins and the enrichment and identification of biotinylated interactors. We describe a variation on the protocol using splitAirID. In this case, AirID is split into two inactive fragments and ligase activity is only restored upon dimerization of the bait proteins. This permits selective detection of proteins that interact with homo- or heterodimeric forms of the bait. The protocol considers design strategies, optimization, and the properties of different biotin ligases to identify optimal conditions for each experimental question. We also discuss common pitfalls and how to troubleshoot them. These approaches allow proximity biotinylation to be a powerful tool for defining protein interactomes. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Construction and functional validation of AirID fusion proteins Alternate Protocol: Construction and functional validation of splitAirID fusion proteins Support Protocol: Western blot for biotinylated proteins Basic Protocol 2: Biotinylation, enrichment, and identification of protein interactors.
Topics: Biotin; Biotinylation; Proteins; Blotting, Western; Ligases
PubMed: 36939277
DOI: 10.1002/cpz1.702 -
The Journal of Biological Chemistry Apr 1949
Topics: Biotin; Proteins
PubMed: 18116978
DOI: No ID Found -
Journal of Controlled Release :... May 2023Pulmonary delivery offers a non-invasive route for the administration of biotherapeutics. In this context, understanding and control of a transport into, and across...
Pulmonary delivery offers a non-invasive route for the administration of biotherapeutics. In this context, understanding and control of a transport into, and across cellular barriers is central to the design of delivery systems. Here, we report our study on receptor mediated delivery of protein cargo by a formulation comprising sub-300 nm sized non-covalent protein complexes with biotin-conjugated PEG-poly(glutamic acid) (biotin-PEG-b-GA) and PEG-b-GA copolymers blend as targeting and complexing functionalities. Designed complexes achieve intracellular delivery of the cargo in lung derived A549 epithelial cells in vitro via sodium-dependent multivitamin transporter (biotin receptor). We further show that biotin receptor driven endocytosis preferentially involves dynamin- and caveolae-dependent vesicular internalization, switching the transport pathway away from predominantly clathrin-dependent entry of free protein. Significantly for a protective intracellular delivery of biotherapeutics based on non-covalent complexation with polymeric excipients, the study provides evidence of intracellular presence of the complexing copolymer; demonstrated exploiting biotin in biotin-PEG-b-GA copolymer as a tag for binding with fluorescently labelled avidin. Moreover, analysis of intracellular localization of constitutive species shortly following cellular internalization suggests a co-localization of biotin-PEG-b-GA copolymer and protein constitutive species. The study demonstrates intracellular delivery of biotin targeted non-covalent complexes with a protein cargo, the result with important implications in a design of enabling technology platforms for protective, receptor mediated intracellular delivery of biotherapeutics.
Topics: Biotin; Receptors, Growth Factor; Peptides; Avidin; Endocytosis
PubMed: 37028450
DOI: 10.1016/j.jconrel.2023.03.051 -
Applied and Environmental Microbiology Aug 2013To develop the infrastructure for biotin production through naturally biotin-auxotrophic Corynebacterium glutamicum, we attempted to engineer the organism into a biotin...
To develop the infrastructure for biotin production through naturally biotin-auxotrophic Corynebacterium glutamicum, we attempted to engineer the organism into a biotin prototroph and a biotin hyperauxotroph. To confer biotin prototrophy on the organism, the cotranscribed bioBF genes of Escherichia coli were introduced into the C. glutamicum genome, which originally lacked the bioF gene. The resulting strain still required biotin for growth, but it could be replaced by exogenous pimelic acid, a source of the biotin precursor pimelate thioester linked to either coenzyme A (CoA) or acyl carrier protein (ACP). To bridge the gap between the pimelate thioester and its dedicated precursor acyl-CoA (or -ACP), the bioI gene of Bacillus subtilis, which encoded a P450 protein that cleaves a carbon-carbon bond of an acyl-ACP to generate pimeloyl-ACP, was further expressed in the engineered strain by using a plasmid system. This resulted in a biotin prototroph that is capable of the de novo synthesis of biotin. On the other hand, the bioY gene responsible for biotin uptake was disrupted in wild-type C. glutamicum. Whereas the wild-type strain required approximately 1 μg of biotin per liter for normal growth, the bioY disruptant (ΔbioY) required approximately 1 mg of biotin per liter, almost 3 orders of magnitude higher than the wild-type level. The ΔbioY strain showed a similar high requirement for the precursor dethiobiotin, a substrate for bioB-encoded biotin synthase. To eliminate the dependency on dethiobiotin, the bioB gene was further disrupted in both the wild-type strain and the ΔbioY strain. By selectively using the resulting two strains (ΔbioB and ΔbioBY) as indicator strains, we developed a practical biotin bioassay system that can quantify biotin in the seven-digit range, from approximately 0.1 μg to 1 g per liter. This bioassay proved that the engineered biotin prototroph of C. glutamicum produced biotin directly from glucose, albeit at a marginally detectable level (approximately 0.3 μg per liter).
Topics: Acyl Carrier Protein; Biotin; Coenzyme A; Corynebacterium glutamicum; Escherichia coli; Genetic Engineering; Phototrophic Processes; Pimelic Acids
PubMed: 23709504
DOI: 10.1128/AEM.00828-13 -
Nutrients Apr 2019Patients with biotin deficiency present symptoms that are similar to those in patients with acrodermatitis enteropathica (inherent zinc deficiency). However, the...
Patients with biotin deficiency present symptoms that are similar to those in patients with acrodermatitis enteropathica (inherent zinc deficiency). However, the association between biotin and zinc deficiency remains unknown. We have previously shown that epidermal keratinocytes of mice fed zinc-deficient (ZD) diets secreted more adenosine triphosphate (ATP) than those of mice fed zinc-adequate (ZA) diets and that epidermal Langerhans cells are absent in ZD mice. Langerhans cells highly express CD39, which potently hydrolyzes ATP into adenosine monophosphate (AMP). Thus, a lack of Langerhans cells in ZD mice leads to non-hydrolysis of ATP, thereby leading to the development of ATP-mediated irritant contact dermatitis. In this study, we examined if biotin-deficient (BD) mice showed the same underlying mechanisms as those in ZD mice. BD mice showed reduced serum zinc levels, disappearance of epidermal Langerhans cells, and enhanced ATP production in the skin. Consequently, irritant contact dermatitis was significantly enhanced and prolonged in BD mice. In conclusion, the findings of our study showed that biotin deficiency leads to zinc deficiency because of which patients with biotin deficiency show similar symptoms as those with acrodermatitis enteropathica.
Topics: Adenosine Triphosphate; Animal Feed; Animals; Biotin; Body Weight; Dermatitis, Contact; Diet; Female; Homeostasis; Irritants; Mice; Mice, Inbred BALB C; Skin; Zinc
PubMed: 31022908
DOI: 10.3390/nu11040919 -
The AAPS Journal Dec 2012Sodium-dependent multivitamin transporter (SMVT) is a vital transmembrane protein responsible for translocating biotin and other essential cofactors such as pantothenate...
Sodium-dependent multivitamin transporter (SMVT) is a vital transmembrane protein responsible for translocating biotin and other essential cofactors such as pantothenate and lipoate. Unlike primary cultures of corneal and retinal pigment epithelial (RPE) cells, immortalized cells can be subcultured many times, yet maintain their physiological properties. Hence, the purpose of this study was to delineate the functional and molecular aspects of biotin uptake via SMVT on immortalized human corneal epithelial (HCEC) and RPE (D407) cells. Functional aspects of [(3)H] biotin uptake were studied in the presence of different concentrations of unlabeled biotin, pH, temperature, metabolic inhibitors, ions, substrates, structural analogs and biotinylated prodrug (Biotin-Acyclovir (B-ACV)). Molecular identity of SMVT was examined with reverse transcription-polymerase chain reaction. Biotin uptake was found to be saturable in HCEC and D407 cells with K (m) of 296.2 ± 25.9 and 863.8 ± 66.9 μM and V (max) of 77.2 ± 2.2 and 308.3 ± 10.7 pmol/mg protein/min, respectively. Uptake was found to be pH, temperature, energy, and sodium-dependent. Inhibition of biotin uptake was observed in the presence of structural analogs and specific substrates. Further, uptake was lowered in the presence of B-ACV indicating the translocation of biotinylated prodrug by SMVT. A distinct band at 774 bp confirmed the molecular existence of SMVT in both the cells. This study shows for the first time the functional and molecular presence of SMVT in HCEC and D407 cells. Therefore, these cell lines may be utilized as in vitro models to study the cellular translocation of biotin-conjugated prodrugs.
Topics: Acyclovir; Biotin; Cells, Cultured; Dose-Response Relationship, Drug; Epithelium, Corneal; Humans; Hydrogen-Ion Concentration; Prodrugs; Retinal Pigment Epithelium; Reverse Transcriptase Polymerase Chain Reaction; Sodium; Symporters; Temperature
PubMed: 22927035
DOI: 10.1208/s12248-012-9399-5