Two extracellular α-arabinofuranosidases are required for cereal-derived arabinoxylan metabolism by subsp. .

Members of the genus are commonly found in the human gut and are known to utilize complex carbohydrates that are indigestible by the human host. Members of the subsp. taxon can metabolize various plant-derived carbohydrates common to the human diet.

Considerations about the inhibition of monophenolase and diphenolase activities of tyrosinase. Characterization of the inhibitor concentration which generates 50 % of inhibition, type and inhibition constants. A review.

Tyrosinase is a copper oxidase enzyme which catalyzes the first two steps in the melanogenesis pathway, L-tyrosine to L-dopa conversion and, then, to o-dopaquinone and dopachrome. Hypopigmentation and, above all, hyperpigmentation issues can be originated depending on their activity. This enzyme also promotes the browning of fruits and vegetables.

A review of the principles and biotechnological applications of glycoside hydrolases from extreme environments.

It is apparent that Biocatalysts are shaping the future by providing a more sustainable approach to established chemical processes. Industrial processes rely heavily on the use of toxic compounds and high energy or pH reactions, factors that both contributes to the worsening climate crisis. Enzymes found in bacterial systems and other microorganisms, from the glaciers of the Arctic to the sandy deserts of Abu Dhabi, provide key tools and understanding as to how we can progress in the biotechnology sector.

In Search of Complementary Extraction Methods for Comprehensive Coverage of the Metabolome.

is an invaluable research tool for many fields of biology, in particular for the production of recombinant enzymes. However, the activity of many such recombinant enzymes cannot be determined using standard biochemical assays, as often, the relevant substrates are not known, or the products produced are not detectable. Today, the biochemical footprints of such unknown enzyme activities can be revealed via the analysis of the metabolomes of the recombinant clones in which they are expressed, using sensitive technologies such as mass spectrometry.

The effects of substituting red and processed meat for mycoprotein on biomarkers of cardiovascular risk in healthy volunteers: an analysis of secondary endpoints from Mycomeat.

Purpose: Mycoprotein is a relatively novel food source produced from the biomass of Fusarium venenatum. It has previously been shown to improve CVD risk markers in intervention trials when it is compared against total meat. It has not hitherto been assessed specifically for benefits relative to red and processed meat.

A computational approach to optimising laccase-mediated polyethylene oxidation through carbohydrate-binding module fusion.

Plastic pollution is a major global concern to the health and wellbeing of all terrestrial and marine life. However, no sustainable method for waste management is currently viable. This study addresses the optimisation of microbial enzymatic polyethylene oxidation through rational engineering of laccases with carbohydrate-binding module (CBM) domains.

Fungal β-glucan-facilitated cross-feeding activities between Bacteroides and Bifidobacterium species.

The human gut microbiota (HGM) is comprised of a very complex network of microorganisms, which interact with the host thereby impacting on host health and well-being. β-glucan has been established as a dietary polysaccharide supporting growth of particular gut-associated bacteria, including members of the genera Bacteroides and Bifidobacterium, the latter considered to represent beneficial or probiotic bacteria. However, the exact mechanism underpinning β-glucan metabolism by gut commensals is not fully understood.

Targeting tyrosinase in hyperpigmentation: Current status, limitations and future promises.

Hyperpigmentation is a common and distressing dermatologic condition. Since tyrosinase (TYR) plays an essential role in melanogenesis, its inhibition is considered a logical approach along with other therapeutic methods to prevent the accumulation of melanin in the skin. Thus, TYR inhibitors are a tempting target as the medicinal and cosmetic active agents of hyperpigmentation disorder.

Identification of D-arabinan-degrading enzymes in mycobacteria.

Bacterial cell growth and division require the coordinated action of enzymes that synthesize and degrade cell wall polymers. Here, we identify enzymes that cleave the D-arabinan core of arabinogalactan, an unusual component of the cell wall of Mycobacterium tuberculosis and other mycobacteria. We screened 14 human gut-derived Bacteroidetes for arabinogalactan-degrading activities and identified four families of glycoside hydrolases with activity against the D-arabinan or D-galactan components of arabinogalactan.

Substituting meat for mycoprotein reduces genotoxicity and increases the abundance of beneficial microbes in the gut: Mycomeat, a randomised crossover control trial.

Purpose: The high-meat, low-fibre Western diet is strongly associated with colorectal cancer risk. Mycoprotein, produced from Fusarium venanatum, has been sold as a high-fibre alternative to meat for decades. Hitherto, the effects of mycoprotein in the human bowel have not been well considered.

Beyond GalNAc! Drug delivery systems comprising complex oligosaccharides for targeted use of nucleic acid therapeutics.

Nucleic Acid Therapeutics (NATs) are establishing a leading role for the management and treatment of genetic diseases following FDA approval of nusinersen, patisiran, and givosiran in the last 5 years, the breakthrough of milasen, with more approvals undoubtedly on the way. Givosiran takes advantage of the known interaction between the hepatocyte specific asialoglycoprotein receptor (ASGPR) and -acetyl galactosamine (GalNAc) ligands to deliver a therapeutic effect, underscoring the value of targeting moieties. In this review, we explore the history of GalNAc as a ligand, and the paradigm it has set for the delivery of NATs through precise targeting to the liver, overcoming common hindrances faced with this type of therapy.

The Relationship between the IC Values and the Apparent Inhibition Constant in the Study of Inhibitors of Tyrosinase Diphenolase Activity Helps Confirm the Mechanism of Inhibition.

Tyrosinase is the enzyme involved in melanization and is also responsible for the browning of fruits and vegetables. Control of its activity can be carried out using inhibitors, which is interesting in terms of quantitatively understanding the action of these regulators. In the study of the inhibition of the diphenolase activity of tyrosinase, it is intriguing to know the strength and type of inhibition.

Computational Network Inference for Bacterial Interactomics.

Since the large-scale experimental characterization of protein-protein interactions (PPIs) is not possible for all species, several computational PPI prediction methods have been developed that harness existing data from other species. While PPI network prediction has been extensively used in eukaryotes, microbial network inference has lagged behind. However, bacterial interactomes can be built using the same principles and techniques; in fact, several methods are better suited to bacterial genomes.

Cross-feeding interactions between human gut commensals belonging to the and genera when grown on dietary glycans.

Elements of the human gut microbiota metabolise many host- and diet-derived, non-digestible carbohydrates (NDCs). Intestinal fermentation of NDCs salvages energy and resources for the host and generates beneficial metabolites, such as short chain fatty acids, which contribute to host health. The development of functional NDCs that support the growth and/or metabolic activity of specific beneficial gut bacteria, is desirable, but dependent on an in-depth understanding of the pathways of carbohydrate fermentation.

Sulfation of Arabinogalactan Proteins Confers Privileged Nutrient Status to Bacteroides plebeius.

The human gut microbiota (HGM) contributes to the physiology and health of its host. The health benefits provided by dietary manipulation of the HGM require knowledge of how glycans, the major nutrients available to this ecosystem, are metabolized. Arabinogalactan proteins (AGPs) are a ubiquitous feature of plant polysaccharides available to the HGM.

The nutritional impact of replacing dietary meat with meat alternatives in the UK: a modelling analysis using nationally representative data.

Dietary patterns high in meat compromise both planetary and human health. Meat alternatives may help to facilitate meat reduction; however, the nutritional implications of displacing meat with meat alternatives does not appear to have been evaluated. Here, the ninth cycle of the National Diet and Nutrition Survey was used as the basis of models to assess the effect of meat substitution on nutritional intake.

Enzymatic oxidation of oleuropein and 3-hydroxytyrosol by laccase, peroxidase, and tyrosinase.

The oxidation of oleuropein and 3-hydroxytyrosol by oxidases laccase, tyrosinase, and peroxidase has been studied. The use of a spectrophotometric method and another spectrophotometric chronometric method has made it possible to determine the kinetic parameters V and K for each enzyme. The highest binding affinity was shown by laccase.

A comprehensive review on the impact of β-glucan metabolism by Bacteroides and Bifidobacterium species as members of the gut microbiota.

β-glucans are polysaccharides which can be obtained from different sources, and which have been described as potential prebiotics. The beneficial effects associated with β-glucan intake are that they reduce energy intake, lower cholesterol levels and support the immune system. Nevertheless, the mechanism(s) of action underpinning these health effects related to β-glucans are still unclear, and the precise impact of β-glucans on the gut microbiota has been subject to debate and revision.

Plant Glycan Metabolism by Bifidobacteria.

Members of the genus , of which the majority have been isolated as gut commensals, are Gram-positive, non-motile, saccharolytic, non-sporulating, anaerobic bacteria. Many bifidobacterial strains are considered probiotic and therefore are thought to bestow health benefits upon their host. Bifidobacteria are highly abundant among the gut microbiota of healthy, full term, breast-fed infants, yet the relative average abundance of bifidobacteria tends to decrease as the human host ages.

Study of tyrosine and dopa enantiomers as tyrosinase substrates initiating l- and d-melanogenesis pathways.

Tyrosinase starts melanogenesis and determines its course, catalyzing the oxidation by molecular oxygen of tyrosine to dopa, and that of dopa to dopaquinone. Then, nonenzymatic coupling reactions lead to dopachrome, which evolves toward melanin. Recently, it has been reported that d-tyrosine acts as tyrosinase inhibitor and depigmenting agent.

Development of a method to measure laccase activity on methoxyphenolic food ingredients and isomers.

We studied the laccase-catalysed oxygenation of methoxyphenolic food ingredients, such as 2-methoxyphenol (guaiacol) and 2,6-dimethoxyphenol (syringol), isomers such as 3- and 4-methoxyphenol, and 2,3-, 3,4- and 3,5-dimethoxyphenol. These methoxyphenolic substrates generate unstable free radicals, which leads to the erroneous determination of steady state rates. The addition of small quantities of ascorbic acid as coupling reagent generates a lag period because it reduces free radicals to methoxyphenols.

Author Correction: A surface endogalactanase in Bacteroides thetaiotaomicron confers keystone status for arabinogalactan degradation.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Structural and functional analyses of glycoside hydrolase 138 enzymes targeting chain A galacturonic acid in the complex pectin rhamnogalacturonan II.

The metabolism of carbohydrate polymers drives microbial diversity in the human gut microbiome. The selection pressures in this environment have spurred the evolution of a complex reservoir of microbial genes encoding carbohydrate-active enzymes (CAZymes). Previously, we have shown that the human gut bacterium () can depolymerize the most structurally complex glycan, the plant pectin rhamnogalacturonan II (RGII), commonly found in the human diet.