344:. If the fatty acid is an odd-numbered chain, the final product of β-oxidation will be propionyl-CoA. This propionyl-CoA will be converted into intermediate methylmalonyl-CoA and eventually succinyl-CoA, which also enters the TCA cycle.
77:
into fatty acids, more than 75% of the fatty acids are converted back into triacylglycerol, a natural mechanism to conserve energy, even in cases of starvation and exercise.
678:
166:
cleaves the pyrophosphate liberated from ATP to two phosphate ions, consuming one water molecule in the process. Thus the net reaction becomes:
144:
542:
673:
162:
lies near 1. To drive the reaction forward, the reaction is coupled to a strongly exergonic hydrolysis reaction: the enzyme
1076:
353:
300:
After activation by ATP, once inside the mitochondria, the β-oxidation of a fatty acids occurs via four recurring steps:
308:
211:
583:
947:
869:
624:
94:
967:
688:
629:
535:
282:
962:
42:, the main energy supply of living organisms, including bacteria and animals. It includes three major steps:
1061:
810:
805:
791:
766:
129:
1096:
916:
911:
616:
117:
113:
1101:
1066:
1022:
786:
645:
470:
1143:
1040:
745:
721:
683:
482:
253:
198:
159:
90:
1138:
985:
604:
528:
109:
1108:
781:
750:
726:
713:
451:
412:
313:
226:
73:, are released into the bloodstream and circulate throughout the body. During the breakdown of
980:
776:
620:
578:
573:
506:
498:
443:
404:
396:
341:
39:
1003:
490:
386:
233:
located on the inner mitochondrial membrane. The liberated carnitine returns to the cytosol.
74:
957:
839:
163:
70:
248:, an intermediate in fatty acid biosynthesis, in order to prevent futile cycling between
486:
1034:
952:
942:
891:
879:
852:
295:
249:
1132:
906:
593:
391:
374:
285:
in the mitochondria to yield ATP. There is no direct participation of the fatty acid.
121:
520:
416:
143:
886:
856:
661:
633:
86:
183:
The inner mitochondrial membrane is impermeable to fatty acids and a specialized
1012:
874:
245:
220:
31:
1113:
835:
756:
737:
669:
612:
555:
551:
494:
337:
241:
194:
137:
62:
35:
502:
447:
400:
259:
The mitochondrial oxidation of fatty acids takes place in three major steps:
17:
1008:
815:
559:
327:
318:
304:
267:
206:
133:
66:
510:
408:
187:
operates to transport activated fatty acids from cytosol to mitochondria.
263:β-oxidation occurs to convert fatty acids into 2-carbon acetyl-CoA units.
106:
455:
431:
373:
Fujita, Yasutaro; Matsuoka, Hiroshi; Hirooka, Kazutake (November 2007).
1071:
1056:
336:
The final product of β-oxidation of an even-numbered fatty acid is
61:
Initially in the process of degradation, fatty acids are stored in
85:
Fatty acids must be activated before they can be carried into the
93:
occurs. This process occurs in two steps catalyzed by the enzyme
322:
191:
125:
524:
34:
are broken down into their metabolites, in the end generating
432:"The Kinetics of Anaerobic Long Chain Fatty Acid Degradation"
142:
753:(amino acid→pyruvate, acetyl CoA, or TCA intermediate)
158:
This two-step reaction is freely reversible and its
1089:
1049:
1021:
1002:
931:
824:
804:
765:
736:
712:
703:
660:
644:
603:
592:
566:
231:
carnitine acyltransferase (palmitoyltransferase) II
471:"β-Oxidation in fatty acid degradation and beyond"
375:"Regulation of fatty acid metabolism in bacteria"
270:to yield generate reduced NADH and reduced FADH
536:
469:Goepfert, Simon; Poirier, Yves (2007-06-01).
201:. This occurs via a series of similar steps:
132:. The next step is formation of an activated
8:
436:Journal (Water Pollution Control Federation)
46:Lipolysis of and release from adipose tissue
216:located on the outer mitochondrial membrane
1018:
935:
828:
821:
733:
709:
600:
543:
529:
521:
81:Activation and transport into mitochondria
49:Activation and transport into mitochondria
430:Novak, John T.; Carlson, Dale A. (1970).
390:
153:RCOO + CoASH + ATP → RCO-SCoA + AMP + PP
150:The balanced equation for the above is:
101:Formation of an activated thioester bond
65:. The breakdown of this fat is known as
365:
219:Acyl carnitine is shuttled inside by a
179:Transport into the mitochondrial matrix
136:bond between the fatty acyl chain and
332:Production of acyl-CoA and acetyl-CoA
169:RCOO + CoASH + ATP → RCO-SCoA+ AMP +
7:
653:Electron acceptors other than oxygen
25:
475:Current Opinion in Plant Biology
392:10.1111/j.1365-2958.2007.05947.x
674:Substrate-level phosphorylation
277:Reduced cofactors NADH and FADH
229:) is converted to acyl CoA by
1:
1077:Reverse cholesterol transport
477:. Physiology and Metabolism.
354:Reverse cholesterol transport
340:, the entry molecule for the
69:. The products of lipolysis,
38:, the entry molecule for the
729:(protein→peptide→amino acid)
238:Carnitine acyltransferase I
212:carnitine acyltransferase I
1160:
1114:Phospagen system (ATP-PCr)
584:Primary nutritional groups
293:
244:inhibition as a result of
205:Acyl CoA is conjugated to
976:
948:Anoxygenic photosynthesis
938:
902:
870:Pentose phosphate pathway
865:
848:
831:
625:Oxidative phosphorylation
495:10.1016/j.pbi.2007.04.007
164:inorganic pyrophosphatase
95:fatty acyl-CoA synthetase
968:Entner-Doudoroff pathway
630:electron transport chain
617:Pyruvate decarboxylation
283:electron transport chain
225:Acyl carnitine (such as
214:(palmitoyltransferase) I
197:is transported into the
185:carnitine carrier system
30:is the process in which
1062:Sphingolipid metabolism
963:DeLey-Doudoroff pathway
811:carbohydrate catabolism
806:Carbohydrate metabolism
792:Purine nucleotide cycle
266:Acetyl-CoA enters into
1031:Fatty acid degradation
751:Amino acid degradation
379:Molecular Microbiology
147:
28:Fatty acid degradation
1067:Eicosanoid metabolism
1023:Fatty acid metabolism
787:Pyrimidine metabolism
646:Anaerobic respiration
146:
57:Lipolysis and release
1041:Fatty acid synthesis
746:Amino acid synthesis
254:fatty acid synthesis
199:mitochondrial matrix
190:Once activated, the
91:fatty acid oxidation
605:Aerobic respiration
487:2007COPB...10..245G
281:participate in the
110:nucleophilic attack
1109:Ethanol metabolism
1057:Steroid metabolism
782:Nucleotide salvage
714:Protein metabolism
227:Palmitoylcarnitine
148:
1126:
1125:
1122:
1121:
1085:
1084:
998:
997:
994:
993:
981:Xylose metabolism
927:
926:
800:
799:
777:Purine metabolism
722:Protein synthesis
699:
698:
621:Citric acid cycle
579:Metabolic network
574:Metabolic pathway
442:(11): 1932–1943.
342:citric acid cycle
105:The enzyme first
40:citric acid cycle
16:(Redirected from
1151:
1097:Metal metabolism
1019:
1004:Lipid metabolism
936:
829:
822:
734:
710:
636:
601:
545:
538:
531:
522:
515:
514:
466:
460:
459:
427:
421:
420:
394:
370:
128:chain linked to
75:triacylglycerols
71:free fatty acids
21:
1159:
1158:
1154:
1153:
1152:
1150:
1149:
1148:
1129:
1128:
1127:
1118:
1102:Iron metabolism
1081:
1045:
1006:
990:
972:
958:Carbon fixation
923:
898:
861:
844:
840:Gluconeogenesis
813:
808:
796:
768:
761:
732:
705:
695:
656:
640:
628:
595:
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562:
549:
519:
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429:
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157:
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103:
83:
59:
23:
22:
15:
12:
11:
5:
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1123:
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1119:
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1111:
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1083:
1082:
1080:
1079:
1074:
1069:
1064:
1059:
1053:
1051:
1047:
1046:
1044:
1043:
1038:
1035:Beta oxidation
1027:
1025:
1016:
1000:
999:
996:
995:
992:
991:
989:
988:
983:
977:
974:
973:
971:
970:
965:
960:
955:
953:Chemosynthesis
950:
945:
943:Photosynthesis
939:
933:
929:
928:
925:
924:
922:
921:
920:
919:
914:
903:
900:
899:
897:
896:
895:
894:
892:Leloir pathway
884:
883:
882:
880:Polyol pathway
872:
866:
863:
862:
860:
859:
853:Glycogenolysis
849:
846:
845:
843:
842:
832:
826:
819:
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801:
798:
797:
795:
794:
789:
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724:
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691:
686:
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666:
664:
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609:
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581:
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564:
563:
550:
548:
547:
540:
533:
525:
517:
516:
481:(3): 245–251.
461:
422:
385:(4): 829–839.
364:
363:
361:
358:
357:
356:
349:
346:
334:
333:
330:
325:
316:
311:
296:Beta oxidation
294:Main article:
291:
288:
287:
286:
278:
275:
271:
264:
250:beta-oxidation
235:
234:
223:
217:
180:
177:
172:
154:
102:
99:
82:
79:
58:
55:
54:
53:
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24:
14:
13:
10:
9:
6:
4:
3:
2:
1156:
1145:
1142:
1140:
1137:
1136:
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1115:
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1107:
1103:
1100:
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1092:
1088:
1078:
1075:
1073:
1070:
1068:
1065:
1063:
1060:
1058:
1055:
1054:
1052:
1048:
1042:
1039:
1036:
1032:
1029:
1028:
1026:
1024:
1020:
1017:
1014:
1010:
1005:
1001:
987:
986:Radiotrophism
984:
982:
979:
978:
975:
969:
966:
964:
961:
959:
956:
954:
951:
949:
946:
944:
941:
940:
937:
934:
930:
918:
915:
913:
910:
909:
908:
907:Glycosylation
905:
904:
901:
893:
890:
889:
888:
885:
881:
878:
877:
876:
873:
871:
868:
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864:
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854:
851:
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847:
841:
837:
834:
833:
830:
827:
823:
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817:
812:
807:
803:
793:
790:
788:
785:
783:
780:
778:
775:
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770:
764:
758:
755:
752:
749:
747:
744:
743:
741:
739:
735:
728:
725:
723:
720:
719:
717:
715:
711:
708:
702:
690:
687:
685:
682:
680:
677:
676:
675:
671:
668:
667:
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663:
659:
652:
651:
649:
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635:
631:
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614:
611:
610:
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582:
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571:
569:
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557:
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546:
541:
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534:
532:
527:
526:
523:
512:
508:
504:
500:
496:
492:
488:
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472:
465:
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457:
453:
449:
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406:
402:
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331:
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200:
196:
193:
188:
186:
178:
176:
175:
167:
165:
161:
151:
145:
141:
139:
135:
131:
127:
123:
122:pyrophosphate
119:
115:
111:
108:
100:
98:
96:
92:
88:
80:
78:
76:
72:
68:
64:
56:
51:
48:
45:
44:
43:
41:
37:
33:
29:
19:
18:Fat breakdown
1030:
887:Galactolysis
857:Glycogenesis
662:Fermentation
634:ATP synthase
478:
474:
464:
439:
435:
425:
382:
378:
368:
335:
299:
258:
237:
236:
230:
210:
189:
184:
182:
170:
168:
152:
149:
104:
87:mitochondria
84:
60:
27:
26:
1144:Fatty acids
1013:lipogenesis
875:Fructolysis
689:Lactic acid
290:β-oxidation
246:malonyl-CoA
221:translocase
160:equilibrium
114:α-phosphate
52:β-oxidation
32:fatty acids
1139:Metabolism
1133:Categories
836:Glycolysis
769:metabolism
767:Nucleotide
757:Urea cycle
738:Amino acid
727:Catabolism
670:Glycolysis
613:Glycolysis
596:metabolism
556:catabolism
552:Metabolism
360:References
338:acetyl-CoA
242:allosteric
240:undergoes
138:Coenzyme A
63:adipocytes
36:acetyl-CoA
1009:lipolysis
816:anabolism
560:anabolism
503:1369-5266
448:0043-1303
401:0950-382X
328:Thiolysis
319:Oxidation
314:Hydration
305:Oxidation
268:TCA cycle
207:carnitine
134:thioester
107:catalyzes
67:lipolysis
932:Nonhuman
917:O-linked
912:N-linked
704:Specific
511:17434787
456:25036816
417:43691631
409:17919287
348:See also
120:to form
89:, where
1072:Ketosis
684:Ethanol
567:General
483:Bibcode
124:and an
112:on the
594:Energy
509:
501:
454:
446:
415:
407:
399:
1090:Other
1050:Other
825:Human
706:paths
452:JSTOR
413:S2CID
814:and
507:PMID
499:ISSN
444:ISSN
405:PMID
397:ISSN
252:and
192:acyl
126:acyl
838:⇄
679:ABE
491:doi
387:doi
323:NAD
321:by
309:FAD
307:by
209:by
195:CoA
130:AMP
118:ATP
116:of
1135::
1011:,
855:⇄
672:→
632:+
623:→
619:→
615:→
558:,
554:,
505:.
497:.
489:.
479:10
473:.
450:.
440:42
438:.
434:.
411:.
403:.
395:.
383:66
381:.
377:.
256:.
171:2P
140:.
97:.
1037:)
1033:(
1015:)
1007:(
818:)
809:(
637:)
627:(
544:e
537:t
530:v
513:.
493::
485::
458:.
419:.
389::
279:2
274:.
272:2
173:i
155:i
20:)
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