Skip to main content

Table 3 Major biochemical determinations performed on cultured skin fibroblasts from patient.

From: A novel mutation of the ACADM gene (c.145C>G) associated with the common c.985A>G mutation on the other ACADM allele causes mild MCAD deficiency: a case report

Metabolic steps Substrates Patient Controls
   (nmol/hr.mg protein) (nmol/hr.mg protein)
Mitochondrial oxidations assayed
- by carbon dioxide production [1,4-14C]-succinatee 3.28 4.08 ± 0.71 (n = 20)
[1-14C]-butyratef 7.37 8.83 ± 1.69 (n = 20)
[1-14C]-octanoateg 1.09 6.75 ± 2.08 (n = 20)
- by carbon dioxide plus water soluble material production [1-14C]-palmitateh 10.59 10.85 ± 2.60 (n = 20)
- by tritiated water formation [9,10-3H]-myristic acid a 0.90b 5.81 ± 2.27 (n = 76)
[9,10-3H]-myristic acid a,c 1.03 8.04 ± 1.74 (n = 20)
[9,10-3H]-palmitic acidd 3.49 9.39 ± 1.70 (n = 20)
Acyl-CoA dehydrogenases
(ETF as an electron acceptor)
  (nmol/min.mg
protein)
(nmol/min.mg
protein)
-VLCAD palmitoyl-CoAi 0.69 1.3 ± 0.5 (n = 55)
-MCAD octanoyl-CoAj 0.48 1.7 ± 0.5 (n = 55)
-SCAD butyryl-CoAk 0.71 1.0 ± 0.4 (n = 55)
Enoyl-CoA hydratases crotonyl-CoA (C4) 307 346 ± 112 (n = 63)
2-dodecenoyl-CoA (C12) 81 78 ± 25 (n = 59)
C12/C4 activity ratio 0.26 0.24 ± 0.05 (n = 59)
β-hydroxyacyl-CoA dehydrogenases acetoacetyl-CoA (C4) 116 99.5 ± 32.1 (n = 105)
β-keto-palmitoyl-CoA (C16) 74 81.8 ± 22.8 (n = 102)
C16/C4 activity ratio 0.64 0.86 ± 0.20 (n = 102)
β-ketoacyl-CoA thiolase β-keto-palmitoyl-CoA (C16) 19.8 20.64 ± 7.79 (n = 47)
acetoacetyl-CoA (no K+) 5.20 6.44 ± 3.46 (n = 60)
acetoacetyl-CoA (with K+) 13.7 13.40 ± 6.22 (n = 60)
activity ratio AA-CoA with   
  K+ on AA-CoA without K+ 2.64 2.17 ± 0.59 (n = 60)
Succinyl-CoA Ketoacid Transferase succinyl-CoA and acetoacetate 10.4 12.11 ± 3.60 (n = 25)
Carnitine palmitoyltransferase
Type I (outer) palmitoyl-CoA 0.53 0.58 ± 0.26 (n = 12)
Type II (inner) palmitoyl-CoA 20.70 15.37 ± 3.13 (n = 8)
Cell membrane carnitine transport L-carnitine 0.73 10-3 0.83 10-3 ±0.25 10-3 (n = 8)
  1. Control values are means ± SD
  2. a Performed by two laboratories; b Conjointly run with fibroblasts from a patient with classical MCADD (homozygous for c.985A>G mutation) and for whom measured activity was 0.4 nmol/hr.mg protein;
  3. c,d Conjointly run with control fibroblasts exhibiting rates of 7.36 and 9.60 nmol/hr.mg protein, respectively; e,f,g,h Concomitantly run with control fibroblasts exhibiting rates of 3.29, 8.10, 4.12 and 11.01 nmol/hr.mg protein, respectively; i,j,k Conjointly run with control fibroblast preparations having activities of 0.70, 1.36 and 0.48 nmol/hr.mg protein, respectively.