2.2: Catabolism of glucose-glycolysis as the first pathway tells us about some general metabolic principles
- Page ID
- 6045
\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)
\( \newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\)
( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\)
\( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)
\( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\)
\( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\)
\( \newcommand{\Span}{\mathrm{span}}\)
\( \newcommand{\id}{\mathrm{id}}\)
\( \newcommand{\Span}{\mathrm{span}}\)
\( \newcommand{\kernel}{\mathrm{null}\,}\)
\( \newcommand{\range}{\mathrm{range}\,}\)
\( \newcommand{\RealPart}{\mathrm{Re}}\)
\( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)
\( \newcommand{\Argument}{\mathrm{Arg}}\)
\( \newcommand{\norm}[1]{\| #1 \|}\)
\( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\)
\( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\AA}{\unicode[.8,0]{x212B}}\)
\( \newcommand{\vectorA}[1]{\vec{#1}} % arrow\)
\( \newcommand{\vectorAt}[1]{\vec{\text{#1}}} % arrow\)
\( \newcommand{\vectorB}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\( \newcommand{\vectorC}[1]{\textbf{#1}} \)
\( \newcommand{\vectorD}[1]{\overrightarrow{#1}} \)
\( \newcommand{\vectorDt}[1]{\overrightarrow{\text{#1}}} \)
\( \newcommand{\vectE}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash{\mathbf {#1}}}} \)
\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)
\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)
Tables of standard free energies of hydrolysis
Table A. Compounds considered to be "High Energy" Compounds
Pi= inorganic phosphate (doesn’t specify a species) = major species at biological pH is \(\mathrm{HPO_{4}^{2-}}\)
| Compound (hydrolysis reaction is shown where more than one is possible) | \(\mathrm{\Delta G^{\circ'}\: (kJ/mol)}\) | Transfer Potential=\(\mathrm{|\Delta G ^{\circ'}|}\) | Compound type | Reason for large \(\mathrm{\Delta G^{\circ'}}\) of hydrolysis S=Substrate P=Product |
|---|---|---|---|---|
| PEP | -61.9 | 61.9 | Enolic phosphate | P tatuomerizes (pyruvate) P resonance stability (Pi) |
| 1,3-bisPGA | -49.3 | 49.3 | Acyl phosphate (phosphoric acid + carboxylic acid) | P ionizaiton (PGA) Increased P resonance stability (Pi and PGA) |
| Phosphocreatine | -43.0 | 43.0 | Guanidine phoshpate | P resonance stability |
| \(\mathrm{ATP \rightarrow AMP + PPi}\) | -45.6 | 45.6 | Phosphoric acid anhydride | P resonance stability P ionization S bond strain due to electrostatic repulsion |
| \(\mathrm{ADP \rightarrow AMP + Pi}\) | -32.8 | 32.8 | Phosphoric acid anhydirde | Same as for \(\mathrm{ATP \rightarrow AMP + P}\) |
| \(\mathrm{ATP \rightarrow ADP + Pi}\) | -30.5 | 30.5 | Phosphoric acid anhydride | Same as for \(\mathrm{ATP \rightarrow AMP + P}\) |
| UDP-Glucose | -31.9 | 31.9 | Sugar nucleotide | P resonance stability P ionization |
| Acetyl Coenzyme A | -31.4 | 31.4 | Thioester | S no resonance stabilization P ionization P resonance stabilization |
| S-adenosylmethionine | -25.6 | 25.6 | Sulfonium salt | Sulfur more stable in P P less charge repulsion |
Table B. Compounds considered NOT to be "High Energy" Compounds
| Compound | \(\mathrm{\Delta G ^{\circ'}\: (kJ/mol)}\) | Transfer Potential | Compound type | Reason for \(\mathrm{\Delta G^{\circ'}}\) of hydrolysis smaller than compounds in Table A. |
| \(\mathrm{AMP \rightarrow adenosine + Pi}\) | -14.2 | 14.2 | Phosphate ester | S no destabilizing electrostatic repulsion P (Adenine) doesn't ionize |
| \(\mathrm{Glc-6-P \rightarrow Glc + HPO_{4}^{2-}}\) | -13.8 | 13.8 | Phosphate ester | S no electrostatic repulsion |
"high energy" bonds are those whose hydrolysis proceeds with \(\mathrm{\Delta G ^{\circ’}}\) more negative than -25kJ/mol
Most values from Principles of Biochemistry pp. 521.
| Systematic | Common |
|---|---|
| ATP:hexose 6-phosphotransferase | Hexokinase |
| ATP:GLC 6-phosphotransferase | Glucokinase (liver) |
| GLC-6-P ketolisomerase | Phosphoglucose isomerase |
| ATP:F-6-P 1-phosphotransferase | Phosphofructokinase-1 (PFK-1) |
| F-1,6-bisP G-3-P-lyase | aldolase |
| G-3-P ketolisomerase | Triose phosphate isomerase |
| G-3-P:(\mathrm{NAD^{+}}\) oxidoreductase (phosphorylating) | G-3-P dehydrogenase |
| ATP:3-PGA 1-phosphotransferase | Phosphoglycerate kinase |
| 3-PGA 2,3-phosphoisomerase | Phosphoglycerate mutase |
| 2-PGA hydro-lyase | Enolase |
| ATP:enol-pyruvate phosphotransferase | Pyruvate kinase |
| Lactate:\(\mathrm{NAD^{+}}\) oxidoreductase | Lactate dehydrogenase |
| Pyruvate carboxy-lyase | Pyruvate decarboxylase |
| Ethanol:\(\mathrm{NAD^{+}}\) oxidoreductase | Alcohol dehydrogenase |
