-
Glycobiology Sep 2022The substitution and de-substitution of carbohydrate materials are important steps in the biosynthesis and/or breakdown of a wide variety of biologically important... (Review)
Review
The substitution and de-substitution of carbohydrate materials are important steps in the biosynthesis and/or breakdown of a wide variety of biologically important polymers. The SGNH hydrolase superfamily is a group of related and well-studied proteins with a highly conserved catalytic fold and mechanism composed of 16 member families. SGNH hydrolases can be found in vertebrates, plants, fungi, bacteria, and archaea, and play a variety of important biological roles related to biomass conversion, pathogenesis, and cell signaling. The SGNH hydrolase superfamily is chiefly composed of a diverse range of carbohydrate-modifying enzymes, including but not limited to the carbohydrate esterase families 2, 3, 6, 12 and 17 under the carbohydrate-active enzyme classification system and database (CAZy.org). In this review, we summarize the structural and functional features that delineate these subfamilies of SGNH hydrolases, and which generate the wide variety of substrate preferences and enzymatic activities observed of these proteins to date.
Topics: Biopolymers; Carbohydrates; Esterases; Hydrolases; Protein Conformation
PubMed: 35871440
DOI: 10.1093/glycob/cwac045 -
ELife Jul 2021Carboxy ester prodrugs are widely employed to increase oral absorption and potency of phosphonate antibiotics. Prodrugging can mask problematic chemical features that...
Carboxy ester prodrugs are widely employed to increase oral absorption and potency of phosphonate antibiotics. Prodrugging can mask problematic chemical features that prevent cellular uptake and may enable tissue-specific compound delivery. However, many carboxy ester promoieties are rapidly hydrolyzed by serum esterases, limiting their therapeutic potential. While carboxy ester-based prodrug targeting is feasible, it has seen limited use in microbes as microbial esterase-specific promoieties have not been described. Here we identify the bacterial esterases, GloB and FrmB, that activate carboxy ester prodrugs in Additionally, we determine the substrate specificities for FrmB and GloB and demonstrate the structural basis of these preferences. Finally, we establish the carboxy ester substrate specificities of human and mouse sera, ultimately identifying several promoieties likely to be serum esterase-resistant and microbially labile. These studies will enable structure-guided design of antistaphylococcal promoieties and expand the range of molecules to target staphylococcal pathogens.
Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; Carboxylesterase; Esterases; Esters; Humans; Hydrolysis; Mice; Prodrugs; Staphylococcus; Staphylococcus aureus
PubMed: 34279224
DOI: 10.7554/eLife.66657 -
Biotechnology Advances Dec 2022Lipolytic enzymes include triacylglycerol lipases (EC 3.1.1.3) and esterases (EC 3.1.1.1) that catalyze the cleavage and formation of ester bonds. They are potential... (Review)
Review
Lipolytic enzymes include triacylglycerol lipases (EC 3.1.1.3) and esterases (EC 3.1.1.1) that catalyze the cleavage and formation of ester bonds. They are potential industrial biocatalysts because of their broad range of activities on natural and synthetic substrates, high stability in organic solvents, thermal stability, stability in highly acidic and alkaline pH conditions and enantio-, regio- and chemo-selectivity. They also have varied applications in different sectors, among which industrial biotechnology, the production of cleaning agents, and pharmaceuticals are the most important ones. Identifying extremophilic lipolytic enzymes is of paramount interest and is a growing field in academic and industrial research. This review is focused on the current knowledge and future avenues of investigation on lipolytic enzymes sourced from the underexploited archaeal domain. Archaea is a potential source for novel extremophilic enzymes, which have high demand in the industries. The archaeal lipases and esterases are clustered into different families based on their similarity/dissimilarity at the genetic level and protein structures. The updated information on characterized and putative lipase sequences has also been presented in this paper. Common structural scaffolds of archaeal lipases have been deduced and discussed in this review. However, huge diversity at the level of their genetic sequences has yet to be correlated with the structure-function relationship. Based on their biochemical properties, possible applications and future prospective of archaeal lipolytic enzymes have also been proposed.
Topics: Humans; Archaea; Esterases; Lipase; Biotechnology; Catalysis
PubMed: 36307049
DOI: 10.1016/j.biotechadv.2022.108054 -
Biochemistry Jul 2021The hyperthermophilic bacterium encodes an unusual enzyme, Xyn10C-GE15A, which incorporates two catalytic domains, a xylanase and a glucuronoyl esterase, and five...
The hyperthermophilic bacterium encodes an unusual enzyme, Xyn10C-GE15A, which incorporates two catalytic domains, a xylanase and a glucuronoyl esterase, and five carbohydrate-binding modules (CBMs) from families 9 and 22. The xylanase and glucuronoyl esterase catalytic domains were recently biochemically characterized, as was the ability of the individual CBMs to bind insoluble polysaccharides. Here, we further probed the abilities of the different CBMs from Xyn10C-GE15A to bind to soluble poly- and oligosaccharides using affinity gel electrophoresis, isothermal titration calorimetry, and differential scanning fluorimetry. The results revealed additional binding properties of the proteins compared to the former studies on insoluble polysaccharides. Collectively, the results show that all five CBMs have their own distinct binding preferences and appear to complement each other and the catalytic domains in targeting complex cell wall polysaccharides. Additionally, through renewed efforts, we have achieved partial structural characterization of this complex multidomain protein. We have determined the structures of the third CBM9 domain (CBM9.3) and the glucuronoyl esterase (GE15A) by X-ray crystallography. CBM9.3 is the second CBM9 structure determined to date and was shown to bind oligosaccharide ligands at the same site but in a different binding mode compared to that of the previously determined CBM9 structure from . GE15A represents a unique intermediate between reported fungal and bacterial glucuronoyl esterase structures as it lacks two inserted loop regions typical of bacterial enzymes and a third loop has an atypical structure. We also report small-angle X-ray scattering measurements of the N-terminal CBM22.1-CBM22.2-Xyn10C construct, indicating a compact arrangement at room temperature.
Topics: Bacterial Proteins; Binding Sites; Caldicellulosiruptor; Crystallography, X-Ray; Enzyme Stability; Esterases; Models, Molecular; Oligosaccharides; Polysaccharides; Protein Conformation; Temperature; Xylosidases
PubMed: 34180241
DOI: 10.1021/acs.biochem.1c00305 -
Methods in Enzymology 2022As a class of enzymes, esterases have been investigated for decades and have found use in industrial processes, synthetic organic chemistry, and elsewhere. Esters are...
As a class of enzymes, esterases have been investigated for decades and have found use in industrial processes, synthetic organic chemistry, and elsewhere. Esters are functional groups composed of an alcohol moiety and a carboxylic acid moiety. Although much work has explored the influence of the carboxyl moiety of an ester on its susceptibility to esterases, little work has explored the influence of the alcohol moiety. Here, we describe an in vitro methodology to explore the influence of changing the alcohol moiety of an ester on its enzymatic hydrolysis, including strategies for analyzing such data. We then describe leveraging data from these assays to develop targeted antimicrobial prodrugs that activate in certain species due to the discriminatory activity of species-specific esterases. We envisage the potential of genomics and machine learning to further these efforts. Finally, we anticipate the potential future uses of these ideas, including developing targeted anti-cancer compounds.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Esterases; Esters; Hydrolysis; Prodrugs
PubMed: 35331374
DOI: 10.1016/bs.mie.2021.11.008 -
Applied and Environmental Microbiology Dec 2016A carbohydrate esterase called glucuronoyl esterase (GE) was discovered 10 years ago in a cellulolytic system of the wood-rotting fungus Schizophyllum commune Genes... (Review)
Review
A carbohydrate esterase called glucuronoyl esterase (GE) was discovered 10 years ago in a cellulolytic system of the wood-rotting fungus Schizophyllum commune Genes coding for GEs were subsequently found in a number of microbial genomes, and a new family of carbohydrate esterases (CE15) has been established. The multidomain structures of GEs, together with their catalytic properties on artificial substrates and positive effect on enzymatic saccharification of plant biomass, led to the view that the esterases evolved for hydrolysis of the ester linkages between 4-O-methyl-d-glucuronic acid of plant glucuronoxylans and lignin alcohols, one of the crosslinks in the plant cell walls. This idea of the function of GEs is further supported by the effects of cloning of fungal GEs in plants and by very recently reported evidence for changes in the size of isolated lignin-carbohydrate complexes due to uronic acid de-esterification. These facts make GEs interesting candidates for biotechnological applications in plant biomass processing and genetic modification of plants. This article is a brief summary of current knowledge of these relatively recent and unexplored esterases.
Topics: Esterases; Fungal Proteins; Glucuronic Acid; Models, Molecular; Schizophyllum; Substrate Specificity
PubMed: 27694239
DOI: 10.1128/AEM.02396-16 -
Journal of Dairy Science Mar 1977The secretion of pregastric esterase and other oral lipases has been detected in 13 species. Research on secretion by the human, calf, kid goat, lamb, and rat of... (Comparative Study)
Comparative Study Review
The secretion of pregastric esterase and other oral lipases has been detected in 13 species. Research on secretion by the human, calf, kid goat, lamb, and rat of pregastric esterase has been significant. Secretion by calves is little affected by age or diet but is greater when calves are nipple fed than when pail fed. Whole milk sham-fed to calves exhibits immediate, sharp decreases in pH and rennet coagulation time resulting from liberation of free fatty acids by pregastric esterase. Bacterial counts in sham-fed products are higher than in control (nonfed) products, but during subsequent incubation bacterial numbers increase less rapidly in sham-fed products. Calf pregastric esterase is a major fat digestive enzyme in young calves but gradually becomes subsidiary to pancreatic lipase as secretion of the latter develops with age. Calf, kid goat, and lamb pregastric esterase exhibits optimum activity on milk fat but is capable of splitting other dietary fats. Data on oral and "gastric" lipases in calves, humans, and rats suggests that gastric lipase is oral lipase. Data on pH and temperature optima as well as activation and inhibition of oral lipases is contradictory but appears to vary considerably between species. Calf pregastric esterase exhibits a unique specificity for fatty acids 4:0 to 10:0 and preferentially hydrolyzes the primary ester position of glycerin. Preparations of calf, kid goat, and lamb pregastric esterase are used commercially to impar typical flavors to Italian-type and Feta cheeses and to accelerate flavor development in other cheeses and cheese-like products. Butterfat modified by pregastric esterase is utilized to impart dairy flavor character to a wide range of processed foods. Treatment with pregastric esterase of calf scours and human malabsorption of syndrome also has been reported.
Topics: Abomasum; Animals; Cattle; Cheese; Diet; Esterases; Fatty Acids, Nonesterified; Gastric Mucosa; Goats; Humans; Lipase; Milk; Mouth; Pancreas; Pharynx; Rats; Saliva; Salivary Glands; Sheep; Tongue
PubMed: 321489
DOI: 10.3168/jds.S0022-0302(77)83873-3 -
International Journal of Molecular... Dec 2022Cold environments characterised by diverse temperatures close to or below the water freezing point dominate about 80% of the Earth's biosphere. One of the survival... (Review)
Review
Cold environments characterised by diverse temperatures close to or below the water freezing point dominate about 80% of the Earth's biosphere. One of the survival strategies adopted by microorganisms living in cold environments is their expression of cold-active enzymes that enable them to perform an efficient metabolic flux at low temperatures necessary to thrive and reproduce under those constraints. Cold-active enzymes are ideal biocatalysts that can reduce the need for heating procedures and improve industrial processes' quality, sustainability, and cost-effectiveness. Despite their wide applications, their industrial usage is still limited, and the major contributing factor is the lack of complete understanding of their structure and cold adaptation mechanisms. The current review looked at the recombinant overexpression, purification, and recent mechanism of cold adaptation, various approaches for purification, and three-dimensional (3D) crystal structure elucidation of cold-active lipases and esterase.
Topics: Esterases; Lipase; Cold Temperature
PubMed: 36499718
DOI: 10.3390/ijms232315394 -
European Journal of Pharmaceutical... Oct 2018Corneal esterases are utilized in the activation of topically applied ester prodrugs. Esterases may also be involved in the metabolism of drugs in posterior eye tissues,...
Corneal esterases are utilized in the activation of topically applied ester prodrugs. Esterases may also be involved in the metabolism of drugs in posterior eye tissues, but their physiological activity is unknown. Furthermore, extrapolation of the esterase activity from protein level to the tissues is missing. The aims of the current study were to determine esterase activities in porcine and albino rabbit ocular tissues, calculate the activities for whole tissues and compare esterase activity between the species. We conducted a hydrolysis study with ocular tissue homogenates using an esterase probe substrate 4-nitrophenyl acetate. The hydrolysis rates were first normalized to protein content and then scaled to whole tissues. The hydrolytic rate normalized to protein content was high in the cornea and iris-ciliary body and low in the lens and aqueous humor, and in general, the rabbit tissues had higher hydrolytic rates than the porcine ones. Esterase activity scaled to whole tissue was high in cornea and iris-ciliary body and low in aqueous humor and retinal pigment epithelium in both species. The current study revealed differences in esterase activities among the ocular tissues and the species. This basic knowledge on ocular esterases provides background information particularly for posterior segment drug development.
Topics: Animals; Enzyme Activation; Esterases; Eye; Female; Hydrolysis; Male; Nitrophenols; Rabbits; Species Specificity; Swine
PubMed: 30030098
DOI: 10.1016/j.ejps.2018.07.034 -
Molecules (Basel, Switzerland) Mar 2021Lipases and esterases are important catalysts with wide varieties of industrial applications. Although many methods have been established for detecting their activities,...
Lipases and esterases are important catalysts with wide varieties of industrial applications. Although many methods have been established for detecting their activities, a simple and sensitive approach for picogram detection of lipolytic enzyme quantity is still highly desirable. Here we report a lipase detection assay which is 1000-fold more sensitive than previously reported methods. Our assay enables the detection of as low as 5 pg and 180 pg of lipolytic activity by direct spotting and zymography, respectively. Furthermore, we demonstrated that the detection sensitivity was adjustable by varying the buffering capacity, which allows for screening of both high and low abundance lipolytic enzymes. Coupled with liquid chromatography-mass spectrometry, our method provides a useful tool for sensitive detection and identification of lipolytic enzymes.
Topics: Chromatography, Liquid; Chromogenic Compounds; Electrophoresis, Polyacrylamide Gel; Enzyme Assays; Esterases; Lipase; Lipolysis; Mass Spectrometry; Substrate Specificity
PubMed: 33799781
DOI: 10.3390/molecules26061542