Table 1
Metabolic pathways that are relevant to MICCP
Metabolism
Reactions
By-product
References
Aerobic oxidation
of organic
compounds
1. CH
3 COO
À
+ 2O
2
! HCO
3
À
+ CO
2 + H
2 O
2. CO
2 + H
2 O
$ H
+
+ HCO
3
À
$ 2H
+
+ CO
3
2+
3. 2H
+
+ CO
3
2+
+ 2OH
À
+ Ca
2+
! CaCO
3
–
[57]
Denitrification
1. CH
2 COO
À
+ 2.6H
+
+ 1.6NO
3
À
! 2CO
2 + 0.8 N
2 + 2.8H
2 O
Complete reaction: H
2 O, N
2 , and CO
2
[58, 59]
2. Ca
2+
+ CO
2 + 2OH
À
! CaCO
3 + H
2 O
Incomplete reaction: H
2 O, NO, N
2 O
Methane oxidation
Anaerobic oxidation: CH
4 + SO
4
2À
+ Ca
2+
! CaCO
3 + H
2 S + H
2 O
Aerobic oxidation: CH
4 + 2O
2
! CO
2 + 2H
2 O
H
2 S
[ 60]
Photosynthesis
2HCO
3
À
+ Ca
2+
! CH
2 O + CaCO
3 + O
2
O
2
[61, 62]
Sulfate reduction
SO
4
2À
+ 2[CH2O] + OH
À
+ Ca
2+
! CaCO
3 + CO
2 + 2H
2 O + HS
À
CO
2 , H
2 O, and HS
À
[62]
Ureolytic
CO(NH
2 )
2 + 2H
2 O + Ca
2+
+ Cell
! 2NH
4
+
+ Cell-CaCO
3
NH
4
+
[63, 64]
Adapted with modification from Zhu and Dittrich [6]
302
G. Mamo and B. Mattiasson