Hemiacetal can undergo ring opening reaction: this is designated the reducing end of the disaccharide. Non-reducing end

Which of these are reducing sugars? Which are non- reducing?

Figure 11-13Electron micrograph of the cellulose fibers in the cell wall of the alga Chaetomorpha melagonium.

Figure 11-14The primary structure of cellulose. Page 365 What is this linkage?

Figure 11-15Proposed structural model of cellulose. Page 365

Plant cell wall architecture extensin Pectins Cellulose

Common sugars found in plant polysaccharides

A spotted June beetle (Pelidnota punctata), showing its surface armor (exoskeleton) of chitin.

Figure 11-16Structure of chitin. Page 366 O O Linkage?

Figure 11-17a  -Amylose. The D-glucose residues of  -amylose are linked by  (1  4) bonds (red). Page 366

Figure 11-17b  -Amylose. This regularly repeating polymer forms a left- handed helix. Page 366

Figure 11-18aAmylopectin. Its primary structure near one of its  (1  6) branch points (red). Page 367

Figure 11-18b Amylopectin. (b) Its bushlike structure with glucose residues at branch points indicated in red. Page 367

Figure 11-20The disaccharide repeating units of the common glycosaminoglycans. Page 368

Figure 11-29aN-Linked oligosaccharides. (a) All N-glycosidic protein attachments occur through a  -N-acetylglucosamino–Asn bond to Asn–X–Ser/Thr. Page 376

Figure 11-29c N-Linked oligosaccharides. (c) Some examples of N- linked oligosaccharides. Page 376

Figure 11-30Some common O-glycosidic attachments of oligosaccharides to glycoproteins (red). Page 376

Hemagglutinin binding to sialic acid- containing receptor. Watch a layperson’s video of flu infectionWatch a layperson’s video of flu infection

FIGURE 7-35 Roles of oligosaccharides in recognition and adhesion at the cell surface.

Figure 11-33aThe surfaces of (a) a normal mouse cell as seen in the electron microscope. (b) a cancerous cell as seen in the electron microscope. Page 378 a b Agglutinated with Conconavalin A--specific for glc and man

Sugar determination by acetylation followed byGC/MS minutes MCountsgal SMS 40:650 40:650 Gas chromatogram of D- galactitol hexacetate Spectrum of Galactitol-1,2,3,4,5,6- hexacetate

FIGURE 7-37 Separation and quantification of the oligosaccharides in a group of glycoproteins. A mixture of proteins extracted from kidney tissue was treated to release oligosaccharides from glycoproteins, and the oligosaccharides were analyzed by matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). Each distinct oligosaccharide produces a peak at its molecular mass, and the area under the curve reflects the quantity of that oligosaccharide.

LEHNINGER PRINCIPLES OF BIOCHEMISTRY Fifth Edition David L. Nelson and Michael M. Cox © 2008 W. H. Freeman and Company CHAPTER 13 Bioenergetics and Biochemical Reaction Types

Living cells are not at equilibrium! Concentrations of reactants and products are typically far from the equilibrium values (Q  K eq ). We must consider “steady state” concentrations of these species for the determination of  G.  G =  G o' + RTlnQ

Homeostatic conditions

Fig 16.2

See Figure 16.3 Catabolic pathways Anabolic pathways

Figure 16.20

The energy charge of most cells ranges from 0.8 to 0.95

Page 567 Figure 16-21b Some overall coupled reactions involving ATP. (b) The phosphorylation of ADP by phosphoenolpyruvate to form ATP and pyruvate.

Oxidized cofactors Reduced cofactors Reduced substratesOxidized substrates + +

Fig 17.3

The Rossman fold. Structural motif is found in the NAD-binding site of many dehydrogenases. (a) Consists of a pair of structurally similar motifs, with three parallel β sheets and two α helices (β-α-β-α-β). (b) Nucleotide-binding domain of lactate dehydrogenase with NAD (ball-and-stick structure) bound in an extended conformation through hydrogen bonds and salt bridges to the paired β-α-β-α-β motifs of the Rossman fold (shades of green).

“Alfonse, Biochemistry makes my head hurt!!” \