Table 25-2Sphingolipid Storage Diseases. Page 979
Figure The breakdown of sphingolipids by lysosomal enzymes. Page 978
Figure 25-90Model for G M2 -activator protein–stimulated hydrolysis of ganglioside G M2 by hexosaminidase A. Page 978
Figure 25-91Cytoplasmic membranous body in a neuron affected by Tay–Sachs disease. Page 979
Chapter 27, Nitrogen Metabolism
Figure 26-1 Forms of pyridoxal-5’-phosphate. (a) Pyridoxine (vitamin B6) and (b) Pyridoxal-5’-phosphate (PLP) (c) Pyridoxamine-5’-phosphate (PMP) and (d) The Schiff base that forms between PLP and an enzyme -amino group.. Page 986
Page 987 Figure 26-2The mechanism of PLP- dependent enzyme-catalyzed transamination.
Figure 26-3The glucose– alanine cycle. Page 988
Figure 26-4 The oxidative deamination of glutamate by glutamate DH.
Page 992 Figure 26-7 The urea cycle.
Figure 26-8The mechanism of action of CPS I. Page 993
Figure 26-9 X-Ray structure of E. coli carbamoyl phosphate synthetase (CPS). Page 993
Figure 26-10The mechanism of action of argininosuccinate synthetase. Page 994
Figure Degradatio n of amino acids to one of seven common metabolic intermediates. Page 995
Figure The pathways converting alanine, cysteine, glycine, serine, and threonine to pyruvate. Page 996
Figure The pathway of phenylalanine degradation. Page 1009
Figure The pathway of phenylalanine degradation. Page 1009
Figure The pathway of phenylalanine degradation. Page 1009
Figure The pteridine ring, the nucleus of biopterin and folate. Page 1009
Page 1010 Figure Formation, utilization, and regeneration of 5,6,7,8- tetrahydrobiopterin (BH 4 ) in the phenylalanine hydroxylase reaction.
Page 1012 Figure 26-30Proposed mechanism of the NIH shift in the phenylalanine hydroxylase reaction.
Page 1013 Figure The NIH shift in the p-hydroxy- phenyl- pyruvate dioxygenase reaction. Homogentisate
Page 1013 Figure Structure of heme.
Figure 26-47Tetrahydrofolate (THF). Page 1028
Figure 26-48The two-stage reduction of folate to THF. Page 1028
Table 26-1Oxidation Levels of C 1 Groups Carried by THF. Page 1028
Page 1029 Figure Interconversion of the C 1 units carried by THF.
Figure 26-50The biosynthetic fates of the C 1 units in the THF pool. Page 1029
Page 1031 Figure The sequence of reactions catalyzed by glutamate synthase.
Table 26-2Essential and Nonessential Amino Acids in Humans. Page 1030 We can’t make these! We can make these!
Page 1033 Figure The syntheses of alanine, aspartate, glutamate, asparagine, and glutamine.
Figure 26-55aX-Ray structure of S. typhimurium glutamine synthetase. (a) View down the 6-fold axis of symmetry showing only the six subunits of the upper ring in alternating blue and green. Page 1034
Page 1035 Figure The regulation of bacterial glutamine synthetase.
Figure 26-57The biosynthesis of the “glutamate family” of amino acids: arginine, ornithine, and proline. Page 1036
Figure 26-58The conversion of 3- phosphoglycerate to serine. Page 1037
Figure 26-66Photograph showing the root nodules of the legume bird’s foot trefoil. Page 1046
Figure 26-67X-Ray structure of the A. vinelandii nitrogenase in complex with ADP · AlF 4 . Page 1046
Figure 26-69The flow of electrons in the nitrogenase- catalyzed reduction of N 2. Page 1048
Figure 26-59aCysteine biosynthesis. (a) The synthesis of cysteine from serine in plants and microorganisms. Page 1038
Figure 26-59bCysteine biosynthesis. (b) The 8-electron reduction of sulfate to sulfide in E. coli. Page 1038
Figure 26-60The biosynthesis of the “aspartate family” of amino acids: lysine, methionine, and threonine. Page 1039
Table 26-3Differential Control of Aspartokinase Isoenzymes in E. Coli. Page 1041
Figure 26-61The biosynthesis of the “pyruvate family” of amino acids: isoleucine, leucine, and valine. Page 1040
Figure 26-62The biosynthesis of chorismate, the aromatic amino acid precursor. Page 1042
Figure 26-63The biosynthesis of phenylalanine, tryptophan, and tyrosine from chorismate. Page 1043
Figure 26-64A ribbon diagram of the bifunctional enzyme tryptophan synthase from S. typhimurium Page 1044
Figure 26-65The biosynthesis of histidine. Page 1045