Biomedical Engineering Reference
In-Depth Information
Glucose
Out
ATP
ADP
1
Glucose-6-P
2
Fructose-6-P
ATP
2
In
3
ADP
Fructose-1,6-DP
4
5
Glyceraldehyde-3-P
(2)
NAD
+
(2)
NADH+2H
Dihydroxyacetone-P
(2)
P
i
6
(2)
NADH+2H
+
(2)
1,3-Phosphoglycerate
ADP
7
ATP
(2)
3-Phosphoglycerate
8
(2)
2-phosphoglycerate
9
H
2
O
(2)
Phosphoenolpyruvate
ADP
10
ATP
(2)
Pyruvate
NADH+H
+
11
NAD
+
(2)
Lactate
Fig. 7.1
Embden-Meyerhof-Parnas (EMP) pathway; homolactic fermentation. The final products
of glucose metabolism are in
bold
. (
2
) indicates the formation of two moles of each compound.
1
Glucokinase,
2
glucose-6-phosphate isomerase,
3
phosphofructokinase,
4
fructose 1,6-bisphos-
phate aldolase,
5
triosephosphate isomerase,
6
glyceraldehyde 3-phosphate dehydrogenase,
7
3-phosphoglycerate kinase,
8
phosphoglycerate mutase,
9
enolase,
10
pyruvate kinase,
11
lactate
dehydrogenase
7.3.1
Use of External Acceptors of Electrons
Because the energy yield of heterofermentative metabolism of hexoses is low,
the competitiveness of obligate heterofermentative lactobacilli depends on the
use of external electron acceptors. The practical relevance of the use of external
acceptors of electrons is represented by the substantial modification of the
