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Glucose Bonds

Molecular Structure Of Glucose

Molecular Structure Of Glucose

What I wanted to do in this video is familiarize ourselves with one of the most important molecules in biology And that is Glucose sometimes referred to as Dextrose and the term Dextrose comes from the fact that the form of Glucose typically Typically found in nature if you form a solution of it, it's going to polarize light to the right and Dextre means Right But the more typical term glucose this literally means sweet in greek if you ask a greek friend to say sweet it sounds like Lucas or I'm not saying it perfectly, but it sounds a lot like a glucose And that's because that's where the word comes from and it is super important because it is it is it is how energy [is] stored and transferred in biological systems in fact right [now] when if someone were to talk about your blood your blood sugar they're talking about the glucose content, so when people talk about blood blood sugar they're talking about your they're talking about your glucose content the whole process of photosynthesis this is all about plants using harnessing the [sun's] energy and storing that energy in the form of glucose when we talk about when we talk about things like respiration in our in our cells cellular respiration that's all about taking glucose and using it to full and to create atp's which are the molecular currency of energy Inside of our body, so these are in credit is an incredibly important molecule We can start wreaking chains of glucose to form Glycogen to form Starches this along with another similar another simple sugar fructose you can use to form our table sugar But even glucose by itself is sweet so let's get familiar with it as a molecule so immediately When you look at this is it kind of drawn as a as an open chain we see that we have one two three Actually, let me number thes Continue reading >>

Glucose

Glucose

This article is about the naturally occurring D-form of glucose. For the L-form, see L-Glucose. Glucose is a simple sugar with the molecular formula C6H12O6, which means that it is a molecule that is made of six carbon atoms, twelve hydrogen atoms, and six oxygen atoms. Glucose circulates in the blood of animals as blood sugar. It is made during photosynthesis from water and carbon dioxide, using energy from sunlight. It is the most important source of energy for cellular respiration. Glucose is stored as a polymer, in plants as starch and in animals as glycogen. With six carbon atoms, it is classed as a hexose, a subcategory of the monosaccharides. D-Glucose is one of the sixteen aldohexose stereoisomers. The D-isomer, D-glucose, also known as dextrose, occurs widely in nature, but the L-isomer, L-glucose, does not. Glucose can be obtained by hydrolysis of carbohydrates such as milk sugar (lactose), cane sugar (sucrose), maltose, cellulose, glycogen, etc. It is commonly commercially manufactured from cornstarch by hydrolysis via pressurized steaming at controlled pH in a jet followed by further enzymatic depolymerization.[3] In 1747, Andreas Marggraf was the first to isolate glucose.[4] Glucose is on the World Health Organization's List of Essential Medicines, the most important medications needed in a basic health system.[5] The name glucose derives through the French from the Greek γλυκός, which means "sweet," in reference to must, the sweet, first press of grapes in the making of wine.[6][7] The suffix "-ose" is a chemical classifier, denoting a carbohydrate. Function in biology[edit] Glucose is the most widely used aldohexose in living organisms. One possible explanation for this is that glucose has a lower tendency than other aldohexoses to react nonspecific Continue reading >>

Carbohydrates

Carbohydrates

The stuff of life is amazingly diverse and complex, but it is all based on combinations of simple biological molecules. Biological molecules are often made from chains & rings of carbon. These molecular structures can be represented by "stick drawings" that show the component atoms (e.g., C, H, N, O for carbon, hydrogen, nitrogen, and oxygen respectively) and show the bonds between them as dashes. A single dash ( - ) represents a single bond, and a double dash (=) represents a double bond. Note that some common "groups" are depicted without showing the bonds between them. For example, the hydroxyl group (-OH) consists of a hydrogen atom bonded to an oxygen atom: The hydoxyl group will commonly be bonded to a carbon atom in this fashion: And this structure might be found, for example, as part of a glucose molecule, depicted below. consists of 6 carbon atoms bonded together as a chain with additional atoms of oxygen and hydrogen. Note that the previous structure (a carbon to which two hydrogens and one hydroxyl group are bound) is located at the bottom of this glucose chain where it is written using the notation CH2OH. This glucose chain forms a ring in aqueous solutions, e.g., in body fluids, as shown below. Fructose is another sugar that also has 6 carbons, 12 hydrogens, and 6 oxygen atoms. However, the arrangement of the atoms is different, and this makes it much sweeter than glucose and also affects its ability to combine with other molecules. Another important theme is that single units of biological molecules (monomers) can join to form increasingly complex molecules (polymers). For example, two monosaccharide sugars can also become bound together chemically to form a disaccharide. Sucrose is the disaccharide in common sugar that we buy at the grocery store. The st Continue reading >>

1,4 Glycosidic Bond - The School Of Biomedical Sciences Wiki

1,4 Glycosidic Bond - The School Of Biomedical Sciences Wiki

1,4 glycosidic bond bonds are formed due to condensation reactions betweena hydroxyl residue on carbon-1 andthe anomeric carbon-4 ontwo monosaccharides ( monomers , single units of sugar),to form a disaccharide (2 monomers bound together) and subsequently a polysaccharide ( polymers , or many units of sugars ). A condensation reaction is when water is eliminated to form asimple molecule . Later hydrolysis by water molecules will reform the two originalmonosaccharides. The 1,4 glycosidic bond is formed between the carbon -1 of one monosaccharide and carbon-4 of the other monosaccharide. There are are two typesofglycosidicbonds- 1,4 alpha and 1,4 beta glycosidic bonds. 1,4 alpha glycosidic bonds are formed when the OH on the carbon-1 is below the glucose ring; while 1,4 beta glycosidic bonds are formed when the OH is above the plane [1] . When two alpha D-glucose molecules join together a more commonly occurring isomer of glucose compared to the L-glucose, form a glycosidic linkage , the term is known as a -1,4-glycosidic bond [2] . Jeremy M. Berg, John L. Tymoczko, Lubert Stryer. Biochemistry Seventh Edition Freeman Berg JM, Tymoczko JL, Stryer L. Biochemistry. 5th edition. New York: W H Freeman; 2002. Section 11.2, Complex Carbohydrates Are Formed by Linkage of Monosaccharides. Available from: This page was last modified on 20 October 2017, at 15:37. This page has been accessed 65,909 times. Continue reading >>

The Hydration Of Glucose: The Local Configurations In Sugarwater Hydrogen Bonds

The Hydration Of Glucose: The Local Configurations In Sugarwater Hydrogen Bonds

Received 8th June 2007 , Accepted 6th November 2007 The hydration of a simple sugar is an essential model for understanding interactions between hydrophilic groups and interfacial water molecules. Here I perform first-principles molecular dynamics simulations on a glucose water system and investigate how individual hydroxyl groups are locally hydrated. I demonstrate that the hydroxyl groups are less hydrated and more incompatible with a locally tetrahedral network of hydrogen bonds than previously thought. The results suggest that the hydroxyl groups form roughly two hydrogen bonds. Further, I find that the local hydration of the hydroxyl groups is sensitively affected by seemingly small variations in the local electronic structure and bond polarity of the groups. My findings offer insight into an atomic-level understanding of sugarwater interactions. A detailed description of hydrogen bonds (H-bonds) is the key to understanding the properties of any H-bonded system. A perfect example is liquid water , which is held together by a three-dimensional, locally tetrahedral network of H-bonds. 13 From a physicochemical standpoint, an H-bond can basically be viewed as a special kind of dipoledipole interaction or as an interaction between bond dipoles. 4,5 Hence, polar groups such as hydroxyl groups can readily form H-bonds with highly polar water molecules. Over the last half-century, hydroxyl groups of simple sugars, or monosaccharides , have generally been assumed to mimic the locally tetrahedral character of the H-bond network in liquid water with a little distortion because they contain a fragment of a water molecule. 69 However, there are some computational studies suggesting that the hydroxyl groups are not as hydrated as they could potentially be. 1012 Here I perform Continue reading >>

Structure Of Glucose And Other Carbohydrate Molecules

Structure Of Glucose And Other Carbohydrate Molecules

Molecular structure of glucose and other carbohydrates To the right of this page I have put a number of links to other files on this website showing 3-D molecules of carbohydrates, which offer the opportunity to see and interact with these molecular models in 3 dimensions. At the bottom of the page there are also links to related topics at this level on the BioTopics website Glucose is an example of a carbohydrate which is commonly encountered. It is also known as blood sugar, and dextrose. Its chemical formula is C6H12O6, and this empirical formula is shared by other sugars - called hexoses - 6 carbon sugars. You may wish to know in some detail how these 24 atoms are arranged in the molecule of glucose the structural formula. In some books you may see diagrams of the glucose molecule looking like this: This so-called stick diagram really only describes how things are in dry (powder) glucose. In life - in your blood and inside cells of plants and animals - most of the glucose consists of molecules shaped into a ring (actually a 6-sided figure, a hexagon) which may be drawn with this fairly simple format: Note that there is an oxygen atom forming part of the ring, and that there are simple lines drawn making up the rest of the ring, and a section sticking out to one side. These lines represent carbon atoms, and -H and -OH groups, most of which have been left out for simplicity. Sometimes the details of just some of these -H and -OH gr oups are drawn in at one end (or both ends). This is because the orientation of these groups slightly alters the chemistry of the molecule, so the resulting molecules are given different names. In alpha glucose the -H group of the rightmost Carbon atom (C1) is above the plane of the ring, whereas it projects below the ring in beta glucose. Continue reading >>

Carbohydrates

Carbohydrates

Monosaccharides Carbohydrates are the most abundant biomolecule on Earth. Living organisms use carbohydrates as accessible energy to fuel cellular reactions and for structural support inside cell walls. Cells attach carbohydrate molecules to proteins and lipids, modifying structures to enhance functionality. For example, small carbohydrate molecules bonded to lipids in cell membranes improve cell identification, cell signaling, and complex immune system responses. The carbohydrate monomers deoxyribose and ribose are integral parts of DNA and RNA molecules. To recognize how carbohydrates function in living cells, we must understand their chemical structure. The structure of carbohydrates determines how energy is stored in carbohydrate bonds during photosynthesis and how breaking these bonds releases energy during cellular respiration. Biomolecules meet specific structural criteria to be classified as carbohydrates. Simple carbohydrates are modifications of short hydrocarbon chains. Several hydroxyls and one carbonyl functional group modify these hydrocarbon chains to create a monosaccharide, the base unit of all carbohydrates. Monosaccharides consist of a carbon chain of three or more carbon atoms containing a hydroxyl group attached to every carbon except one. The lone carbon atom is double-bonded to an oxygen atom, and this carbonyl group may be in any position along the carbon chain. Therefore, one oxygen atom and two hydrogen atoms are present for every carbon atom in a monosaccharide. Consequently, we can define monosaccharides as possessing the molecular formula (CH2O)n, where n equals the number of carbon atoms and must be greater than or equal to three. Monosaccharides (Greek, meaning “single sugar”) are simple sugars and are frequently named using the suffix Continue reading >>

Covalent Bonds - Molecular Cell Biology - Ncbi Bookshelf

Covalent Bonds - Molecular Cell Biology - Ncbi Bookshelf

Covalent bonds , which hold the atoms within anindividual molecule together, are formed by the sharing of electrons in the outer atomicorbitals. The distribution of shared as well as unshared electrons in outer orbitals is a majordeterminant of the three-dimensional shape and chemical reactivity of molecules. For instance,as we learn in Chapter 3, the shape of proteins iscrucial to their function and their interactions with small molecules. In this section, wediscuss important properties of covalent bonds and describe the structure of carbohydrates toillustrate how the geometry of bonds determines the shape of small biological molecules. Each Atom Can Make a Defined Number of Covalent Bonds Electrons move around the nucleus of an atom in clouds called orbitals,which lie in a series of concentric shells, or energy levels; electrons inouter shells have more energy than those in inner shells. Each shell has a maximum number ofelectrons that it can hold. Electrons fill the innermost shells of an atom first; then theouter shells. The energy level of an atom is lowest when all of its orbitals are filled, and anatoms reactivity depends on how many electrons it needs to complete its outermostorbital. In most cases, in order to fill the outermost orbital, the electrons within it formcovalent bonds with other atoms. A covalent bond thus holds two atoms close together becauseelectrons in their outermost orbitals are shared by both atoms. Most of the molecules in living systems contain only six different atoms: hydrogen, carbon,nitrogen, phosphorus, oxygen, and sulfur. The outermost orbital of each atom has acharacteristic number of electrons: These atoms readily form covalent bonds with other atoms and rarely exist as isolatedentities. As a rule, each type of atom forms a charact Continue reading >>

Glycosidic Bond - An Overview | Sciencedirect Topics

Glycosidic Bond - An Overview | Sciencedirect Topics

Sheo B. Singh, ... Fernando Pelez, in Comprehensive Natural Products II , 2010 The new glycosidic polyketide antibiotic ECO-0501 (70) was discovered from the vancomycin producer A. orientalis ATCC 43491, using a genome-scanning approach for the discovery of novel biosynthetic pathways capable of producing novel metabolites.168 ECO-0501 exhibited activity against Gram-positive bacteria including MRSA and VRE with MICs comparable to those of vancomycin (2gml1). The compound is effective in a mouse model of S. aureus infection and showed a good safety profile. It has been suggested that the compound acts through a novel membrane or cell wall target.169 John W. Pelley, in Elsevier's Integrated Review Biochemistry (Second Edition) , 2012 Glucose forms glycosidic bonds with itself, fructose, and galactose to produce three nutritionally important disaccharides (Fig. 2-7): Maltose: glucose + glucose; product of starch digestion There are three nutritionally important polysaccharides, all of which are composed entirely of glucose: Amylose (-1,4 linkages) has only a linear structure. Amylopectin (-1,4 linkages + -1,6 linkages) has a branched structure; a branch point occurs every 25 to 30 glucose residues (Fig. 2-8). Glycogen has a structure like amylopectin except that it is more highly branched (every 8 to 12 residues of glucose). Cellulose (-1,4 linkages) has an unbranched structure. Structural polysaccharide of plant cells. Important source of fiber in the diet; not hydrolyzed by digestive enzymes; no caloric value. Hyaluronic acid, heparin, and pectin are called heteropolysaccharides, since they are formed from several different sugars, including sugar acids and amino sugars. Sugars with aldehyde groups are also reactive with primary amino groups on proteins. The glycosylat Continue reading >>

Perturbation Of The Intramolecular Hydrogen Bonds Of Glucose By Cu+ Association

Perturbation Of The Intramolecular Hydrogen Bonds Of Glucose By Cu+ Association

Properties, Dynamics, and Electronic Structure of Atoms and Molecules Perturbation of the intramolecular hydrogen bonds of glucose by Cu+ association Departamento de Qumica, C9, Universidad Autnoma de Madrid, Cantoblanco, 28049 Madrid, Spain Departamento de Qumica, C9, Universidad Autnoma de Madrid, Cantoblanco, 28049 Madrid, Spain Please review our Terms and Conditions of Use and check box below to share full-text version of article. I have read and accept the Wiley Online Library Terms and Conditions of Use. Use the link below to share a full-text version of this article with your friends and colleagues. Learn more. Get access to the full version of this article. View access options below. You previously purchased this article through ReadCube. View access options below. Logged in as READCUBE_USER. Log out of ReadCube . A density functional theory study of glucose and glucoseCu+ complexes has been performed to investigate the changes undergone by the set of intramolecular hydrogen bonds of the neutral system upon Cu+ association. The geometries of the different species investigated were optimized at the B3LYP/631G(d,p) level. The same level of theory was used to obtain the harmonic vibrational frequencies and to analyze the electron charge density by means of the atoms in molecules theory. We have shown that the interaction with Cu+ strongly perturbs the set of intramolecular hydrogen bonds of the neutral. Some of these changes are a direct consequence of the conformational changes induced by the metal, which result in the breaking of some of the existing bonds or in the formation of new ones. The most important point, however, is that the intramolecular hydrogen bonds that remain are perturbed to a different extent. In general, all hydrogen bonds in which the OH don Continue reading >>

Disaccharides And Glycosidic Bonds

Disaccharides And Glycosidic Bonds

Monosaccharides such as glucose can be linked together in condensation reactions. For example, sucrose (table sugar) is formed from one molecule of glucose and one of fructose, as shown below. Molecules composed of two monosaccharides are called disaccharides. Click on the step numbers to see the steps in the formation of sucrose. Click on the mouse icon at left to clear the steps to see them again. First, two monosaccharides are brought together such that two hydroxyl groups are close to each other. Note that the glucose half of sucrose has the configuration at C1. Glycosidic bonds are labeled or depending on the anomeric configuration of the C1 involved in the glycosidic bond. Maltose, which links two glucose molecules, has an glycosidic bond like sucrose. Lactose, the primary sugar in milk, links glucose and galactose in a glycosidic bond instead. Can glycosidic bonds only be formed between C1 and C4, as in sucrose, maltose, and lactose? Glycosidic bonds can also be formed between other carbons of monosaccharides. For example, several polymers of glucose involve glycosidic bonds between C1 and C6 in addition to bonds between C1 and C4. This fact makes polymers of monosaccharides potentially much more complex than polymers of amino acids (proteins) or nucleotides (DNA), as you will see shortly. Continue reading >>

Structural Biochemistry/carbohydrates

Structural Biochemistry/carbohydrates

Carbohydrates are important macromolecules that consist of carbon, hydrogen, and oxygen. They are organic compounds organized in the form of aldehydes or ketones with multiple hydroxyl groups coming off the carbon chain. Carbohydrates are the most abundant organic compounds in living organisms and account for one of the four major biomolecular classes including proteins, lipids, and nucleic acids. They originate as products from carbon dioxide and water by photosynthesis, (+ reducing agents and energy from photon [sunlight]) where ADP (Adenosine diphosphate) is a product that can be synthesized to form ATP (Adenosine-5'-triphosphate) - a form of chemical energy used in cells which acts as a fuel of metabolism in plants and animals - through aerobic cellular respiration, (+ oxidizing agent and energy from photon [through electrochemical gradient]) Carbohydrates play a variety of extensive roles in all forms of life: The general empirical structure for carbohydrates is (CH2O)n. Monosaccharides, which are simple sugars that serve as fuel molecules as well as fundamental constituents of living organisms, are the simplest carbohydrates, and are required as energy sources. The most commonly known ones are perhaps glucose and fructose. Carbohydrates exist in a variety of isomers forms. Those that differ in arrangements of atoms are known as constitutional isomers, such as glyceradehyde and dihydroxyacetone. Stereoisomers have the same attachments of the atoms, but different in spatial arrangements, which can be further separated into two types: diastereoisomers and enantiomers. Diastereoisomers are the molecules that are not mirror images of each other and enantiomers exists as nonsuperimposable mirror images. The fact that monosacharides can possess up to three different asy Continue reading >>

Carbohydrates

Carbohydrates

Carbohydrates have the general molecular formula CH2O, and thus were once thought to represent "hydrated carbon". However, the arrangement of atoms in carbohydrates has little to do with water molecules. Starch and cellulose are two common carbohydrates. Both are macromolecules with molecular weights in the hundreds of thousands. Both are polymers (hence "polysaccharides"); that is, each is built from repeating units, monomers, much as a chain is built from its links. The monomers of both starch and cellulose are the same: units of the sugar glucose. Sugars Monosaccharides Three common sugars share the same molecular formula: CHO. Because of their six carbon atoms, each is a hexose. They are: glucose, "blood sugar", the immediate source of energy for cellular respiration galactose, a sugar in milk (and yogurt), and fructose, a sugar found in honey. Although all three share the same molecular formula (C6H12O6), the arrangement of atoms differs in each case. Substances such as these three, which have identical molecular formulas but different structural formulas, are known as structural isomers. Glucose, galactose, and fructose are "single" sugars or monosaccharides. Two monosaccharides can be linked together to form a "double" sugar or disaccharide. Disaccharides Three common disaccharides: sucrose — common table sugar = glucose + fructose lactose — major sugar in milk = glucose + galactose maltose — product of starch digestion = glucose + glucose Although the process of linking the two monomers is rather complex, the end result in each case is the loss of a hydrogen atom (H) from one of the monosaccharides and a hydroxyl group (OH) from the other. The resulting linkage between the sugars is called a glycosidic bond. The molecular formula of each of these disacchar Continue reading >>

Monosaccharide - Definition, Function, Structure And Examples | Biology Dictionary

Monosaccharide - Definition, Function, Structure And Examples | Biology Dictionary

A monosaccharide is the most basic form of carbohydrates. Monosaccharides can by combined through glycosidic bonds to form larger carbohydrates, known as oligosaccharides or polysaccharides. An oligosaccharide with only two monosaccharides is known as a disaccharide. When more than 20 monosaccharides are combined with glycosidic bonds, a oligosaccharide becomes a polysaccharide . Some polysaccharides, like cellulose, contain thousands of monosaccharides. A monosaccharide is a type of monomer, or molecule that can combine with like molecules to create a larger polymer. Monosaccharides have many functions within cells. First and foremost, monosaccharides are used to produce and store energy. Most organisms create energy by breaking down the monosaccharide glucose, and harvesting the energy released from the bonds. Other monosaccharides are used to form long fibers, which can be used as a form of cellular structure. Plants create cellulose to serve this function, while some bacteria can produce a similar cell wall from slightly different polysaccharides. Even animal cells surround themselves with a complex matrix of polysaccharides, all made from smaller monosaccharides. All monosaccharides have the same general formula of (CH2O)n, which designates a central carbon molecule bonded to two hydrogens and one oxygen. The oxygen will also bond to a hydrogen, creating a hydroxyl group . Because carbon can form 4 bonds, several of these carbon molecules can bond together. One of the carbons in the chain will form a double bond with an oxygen, which is called a carbonyl group . If this carbonyl occurs at the end of the chain, the monosaccharide is in the aldose family. If the carboxyl group is in the middle of the chain, the monosaccharide is in the ketose family. Above is a pict Continue reading >>

Biodotedu

Biodotedu

Glucose molecules form rings. The first carbon atom (C1), which is an aldehyde group (-CHO), creates a hemiacetal with the fifth carbon atom (C5) to make a 6-membered-ring (termed a pyranose). The atoms in this cyclic molecule then arrange themselves in space to minimize the amount of strain on each of the covalent bonds. The carbon atoms in the glucose ring each have four covalent bonds. The best, or optimum angle, between all these bonds is 109.5o, which results in a perfect tetrahedron. If, for any reason, these bonds are forced into greater, or smaller angles then the molecule will be strained or stressed, and be much less stable. It follows, therefore, that the glucose molecule will be at its most stable when all the carbon atoms can arrange themselves so that their bond angles are all close to 109.5o. Some idea of how these considerations affect the shape of the molecule in space can be seen by examining the molecule cyclohexane (C6H12), which also forms a simple three-dimensional ring in space. The molecule could be drawn out in several different ways, thus: The flat or planar version is the most unlikely since, in this arrangement the carbon bond angles would be at least 120o, which is greater than the optimum. Also, in this form, every carbon atom is lined up with every other carbon atom, that forces the hydrogen atoms to also line up, or eclipse one another. This puts the molecule under a lot of strain. In the boat conformation some of these strains are lessened, and many of the bond angles are much closer to the optimum degree, however two of the hydrogen atoms at the front and back of the "boat" are forced very close to one another (this is called "steric hinderance", and this arrangement is still stressful. Moving one end of the "boat" downwards produces t Continue reading >>

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