Enzymes Referred to in Chapter

Trivial name and name used in this volume 

P-D-2-Acetamido-2-deoxy-hexosidase Acetylcholinesterase Adenosine 3, 5 -phosphate phosphodiesterase Aldose-ketose isomerases (general) 

Amylo-1,6-D-glucosidase Arabinanase Arylsulphatase 4-L-Aspartyl-P-D-glucosylamine amidohydrolase Bromelain (juice) Bromelain (stem) Carbohydrate isomerases Carbohydrate transferases Carboxypeptidases A—C Carboxypeptidase Y Cellobiase 

2-Acetamido-2-deoxy-p-D-galacto-side acetamidodeoxygalacto-hydrolase see Chitinase 

2-Acetamido-2-deoxy-P-D-glucoside acetamidodeoxyglucohydrolase 2-Acetamido-2-deoxy-P-D-hexoside acetamidodeoxyhexohydrolase see Cholinesterase 

Trivial name and name used in this volume Systematic name E.C. No. Page 

D-glucanotransf erase D-glucano)-transf erase (cyclizing)  

402 Tani, M. Ohtsuru, and T. Hata, Agric. and Biol. Chem. Japan), 1974, 38, 1617. See Introduction (Part II, Chapter 1, p. 207). 

Three new fucolipids (4)—(6), two of which exhibited blood-group A activity, have been isolated from the water-soluble glycolipids of hog gastric mucosa.  

Partial hydrolysis with acid and methylation analysis were used in elucidating their structures. A difucosylglycolipid that exhibited blood-group A activity was also isolated from the same source the structure (7) of this glycolipid was established by means of partial hydrolysis with acid, sequential degradation with specific glycosidases, and methylation studies.  

2-Acetamido-2-deoxy-a-D-galacto- 3.2.1.49 side acetamidodeoxygalacto-hydrolase 

Heparan sulphate lyase Heparan sulphate lyase 4.2.2.S 385 

2-Acetamido-2-deoxy-a-D-galactoside acetamido-deoxygalactohydrolase 2-Acetamido-2-deoxy-j3-D-galactoside acetamidodeoxy-galactohydrolase D-Mannosyl-glycoprotein 1,4-A -acetamidodeoxy-/3-D-glycohydrolase (see also Chitinase, EC 3.2.1.14) 

Carbohydrate isomerases Carbohydrate oxidases Carboxypeptidase A Carboxypeptidase B 

Carboxypeptidase Y Cathepsin D Cell lytic enzyme Cellobiose oxidase Cellulase 

---

The enzymes referred to in the chapters of this review are listed in alphabetical order generally under their recommended names as in ENZYME NOMENCLATURE... 

Enzymic methods were used to link a-D-glucopyranose to the anomeric positions of a-D-lyxopyranose and P-D-xylulose. Various dichloro-dideoxy sucroses and products derived by selective nucleophilic displacement of single chlorine atoms are referred to in Chapter 8. Trehalose derivatives carrying long-chain branched fatty acid residues are referred to in Chapter 19. 

Other reports on glycogen and glycogen-metabolizing enzymes are referred to in Chapters 4 and 6, respectively. 

Starting from L-arabinose is noted in Chapter 24. A synthesis of the enzyme inhibitor 2-deoxy- -KDO is referred to in Chapter 16. 

A 2,4,6-trideoxy-6-iodo-hexose derivative prepared from D-glucose also with potential as a chiral intermediate for synthesizing inhibitors of this enzyme is mentioned in Chapters 7 and 11. The synthesis of spirobis-1,4-dioxans from 2-chloroethyl fructopyran-oside is mentioned in Chapter 3 (ref.6), and the formation of tricyclic pyrone derivatives from unsaturated sugars is referred to in Chapter 12 (ref.31). 

A number of other enzymes that act on DNA and RNA are an important part of recombinant DNA tech-nology. Many of these are referred to in this and subsequent chapters (Table 40-3). 

The role of anthocyanidin synthase (ANS) in the biosynthetic pathway is to catalyze reduction of the leucoanthocyanidins to the corresponding anthocyanidins. However, in vivo it is anthocyanidins in pseudobase form that are formed, as is described below. In this chapter, use of anthocyanidin should be taken to include the pseudobase form. Furthermore, although the name ANS is commonly used, the enzyme is also referred to in the literature as leucoantho-cyanidin dioxygenase (LDOX), reflecting the reaction type. 

After presenting the criteria for performance evaluation of the three different techniques, we explain their meaning and significance. In the next section, we will comment on the appropriateness of the criteria and the reference points. This discussion relates to coverage of enzyme performance criteria in Chapter 2. Jacobsen and Finney suggest the following five criteria for comparison of performance ( Jacobsen s five criteria ) ... 

They act as antipathogenic agents and thus affect the process of pathogenesis. They may act on the host through the Induction of plant resistance mechanisms such as stimulation of lignification or enhancement of phytoalexin production. (Please refer to the chapter by Salt and Kuc in this volume for further discussion of this type of compound.) They may act on the pathogen to accentuate elicitor release or to prevent infection (host penetration), colonization (inhibition of phytotoxin synthesis, extracellular enzyme production and action, or phytoalexin degradation) or reproduction. 

Measurements of enzymes are used in medicine in two major ways Enzymes are measured in serum and other bodily fluids to detect injury to a tissue that makes the enzyme. Enzymes are also measured, often within a tissue, to identify abnormahties or absence of the enzyme, which may cause disease. In the first part of this chapter we discuss enzymes as markers of disease, and then describe conditions associated with abnormalities of enzymes in one readily available cell type, the erythrocyte or red blood cell. Many other abnormahties of enzymes exist, of course, and many are described in chapters of this book including Chapters 40 (Inherited Disease), 43 (Pharmacogenetics) and 55 (Inborn Errors of Amino Acid, Organic Acid, and Fastty Acid Metabolism). For descriptions of enzyme abnormalities associated with lysosomal storage disease, and tests for the related enzymes, readers are referred to the Chapter 40 Appendix that is located on this book s accompanying Evolve site, found at http //evolve.elsevier.com/Tietz/textbook/. 

The second metabolic pathway which we have chosen to describe is the tricarboxylic acid cycle, often referred to as the Krebs cycle. This represents the biochemical hub of intermediary metabolism, not only in the oxidative catabolism of carbohydrates, lipids, and amino acids in aerobic eukaryotes and prokaryotes, but also as a source of numerous biosynthetic precursors. Pyruvate, formed in the cytosol by glycolysis, is transported into the matrix of the mitochondria where it is converted to acetyl CoA by the multi-enzyme complex, pyruvate dehydrogenase. Acetyl CoA is also produced by the mitochondrial S-oxidation of fatty acids and by the oxidative metabolism of a number of amino acids. The first reaction of the cycle (Figure 5.12) involves the condensation of acetyl Co and oxaloacetate to form citrate (1), a Claisen ester condensation. Citrate is then converted to the more easily oxidised secondary alcohol, isocitrate (2), by the iron-sulfur centre of the enzyme aconitase (described in Chapter 13). This reaction involves successive dehydration of citrate, producing enzyme-bound cis-aconitate, followed by rehydration, to give isocitrate. In this reaction, the enzyme distinguishes between the two external carboxyl groups... 

Another example of translational control in eukaryotes is the inhibition of yeast GCN4 protein synthesis by stem-loop structures present in the 50 end of the mRNA. GCN4 control, and an analogous situation in bacteria, links amino-acid biosynthesis to ribosome pausing in the 50 end of the mRNA. This mechanism was first described for the tryptophan operon in E. coli and it is often referred to as attenuation. Transcriptional and translational control of the tryptophan biosynthetic enzymes are described in Chapter 28. 

The time that it takes for the steady state to become established is usually a matter of milliseconds. Therefore it is necessary to use the special high-speed techniques that were referred to in Section 9.11 of the last chapter. The stopped-flow method is frequently used, but the temperature-jump method has also been applied. The procedure is essentially to follow, by spectrophotometric means, the concentration of enzyme-substrate complex or of a reaction product. Then, by applying the theoretical equations to the data it is possible to obtain values for rate constants which could not be obtained from steady-state kinetics. In this way one gains much greater insight into the mechanisms. 

This section focuses on charge transfer in synthetic polymer solid phases (for metal enzymes refer to Chapter 2). In many electronic devices such as electrocatalytic systems, sensors, and electrochromic display or photoconversion systems, charge transfer between redox molecules... 

Poly(ADP-ribosyl)ation is a posttranslational protein modification carried out by a family of enzymes, referred to as poly(ADP-ribose) polymerases (PARPs). The biochemistry of poly(ADP-ribose) formation and degradation, and the molecular and cell biolc of the enzymes involved are described in detail in several other Chapters. However, it is worth summarizing several facts that are particularly relevant for the link between pol)r(ADP-ribosyl)ation and aging. 

---