Krebs mkombero - magawo chachikulu ndi zotsatira kachitidwe kwachilengedwenso

Mtokoma wa mphamvu mpweya mankhwala adzamasulidwa m'mikhalidwe aerobic yokhudza oxygen. The Krebs mkombero umatchedwanso citric acid adzizungulira, kapena foni kupuma. Mu decoding ndi zochita munthu kwa ndondomekoyi panafika asayansi ambiri: A. Szent-Gyorgyi, A. Lehninger, X. The Krebs mkombero ndi dzina, SE Severin ndi ena.

Pakati pa thupi ndi anaerobic kuwonongedwa kwa chakudya pali pafupi correlative ubwenzi. Choyamba, iwo anafotokoza mu kukhalapo kwa asidi pyruvic, amene anamaliza chimbudzi anaerobic chakudya ndipo ayamba kupuma ma (Krebs mkombero). mbali zonse ziwiri catalyzed ndi puloteni chomwecho. The mphamvu mankhwala anamasulidwa ndi phosphorylation, akudikira monga macroergs ATP. Zimene mankhwala nawo ndi coenzymes yemweyo (nad, NADP) ndi cations. Kusiyanaku motere: ngati anaerobic kuwonongedwa kwa chakudya ambiri isanafalikire mu hyaloplasm, ndi ma kupuma zochita zimachitika makamaka mitochondria.

Akamaziwononga pali chidani pakati pa magawo awiri. Choncho, kupezeka kwa mpweya mlingo anachita wa glycolysis amachepetsa yokhudza ufiti (Pasteur zochitika). glycolysis mankhwala akhoza ziletsa kagayidwe aerobic chakudya (Crabtree zochitika).

The Krebs mkombero ndi mndandanda wa zochita mankhwala chifukwa katundu kuwononga chakudya ndi oxidized kuti mpweya woipa komanso madzi, ndi mphamvu mankhwala atasunga mankhwala mphamvu kulemera. Pa kupuma ma amapangidwa "chotengera" - asidi oxaloacetic (SCHOK). Kenako condensation ndi "chotengera" adamulowetsa asidi acetic zotsalira. Pali tricarboxylic asidi - citric. Pa zochita mankhwala, pali "Kulowera" zotsalira ku asidi mkombero acetic. Chifukwa aliyense molekyulu asidi pyruvic aumbike khumi mamolekyulu asidi adenozintrifosfatnoy. Kumapeto kwa mkombero izo anamasulidwa "chotengera" imene amachitira ndi tinthu latsopano asidi adamulowetsa zotsalira acetic.

Krebs mkombero anachita

Ngati mapeto mankhwala a anaerobic chimbudzi chakudya ndi asidi lactic, mchikakamizo cha dehydrogenase lactate ali oxidized kuti pyruvic acid. Part wa mamolekyulu asidi pyruvic ndi kaphatikizidwe "chotengera" SCHOK mukopedwe pyruvate carboxylase enzyme pamaso pa Mg2 + ayoni. mamolekyulu Part pyruvic asidi ndi gwero la "nthochi yogwira" - atsetilkoenzima A (acetyl-CoA). Zimene ikuchitika mchikakamizo cha pyruvate dehydrogenase. Acetyl-CoA lili mphamvu kwambiri ndipo zimenezi amasonkhana padziko 5-7% mphamvu. Zambiri mankhwala mphamvu opangidwa ndi makutidwe ndi okosijeni wa "nthochi wamphamvu".

Kutengera tsitratsintetazy akuyamba bwino ntchito Krebs adzizungulira, imbaenda kuna mapangidwe asidi citrate. Asidiyu zimakhudza akonitat hydratase dehydrogenated ndi n'kukhala CIS-aconitic asidi amene pambuyo Kuwonjezera molekyulu madzi akudutsa mu isocitric. Pakati pa zidulo atatu tricarboxylic zazikulu mgwirizano unakhazikitsidwa.

asidi Isocitric ali oxidized kuti oxalosuccinic, amene decarboxylated ndipo anatembenukira kwa asidi alpha-ketoglutaric. Zimene ali catalyzed ndi isocitrate enzyme. Alpha-ketoglutaric asidi mchikakamizo cha enzyme 2-oxo- (alpha-keto) -glutaratdegidrogenazy decarboxylated, chifukwa mu mapangidwe succinyl-CoA kupanga mphamvu muzikondana.

Mu sitepe yotsatira succinyl-CoA ndi puloteni succinyl-CoA synthetase transmits mphamvu chomangira GDF (guanozindifosfatnoy acid). GTP (guanozintrifosfatnaya acid) mchikakamizo cha adenylate enzyme amatumiza GTP-mphamvu chomangira amp (adenozinmonofosfatnoy acid). Krebs zolimbikitsa: chilinganizo - GTP + amp - GDP + ADP.

asidi Succinic pansi kanthu za enzyme succinate dehydrogenase (LDH) ndi oxidized kuti fumaric. SDG coenzyme ndi flavin adenine dinucleotide. Fumarate mukopedwe fumaratgidratazy enzyme ndi n'kukhala asidi malic, womwe ndi oxidized kupanga SCHOK. Pamaso pa dongosolo yatikhudza acetyl-CoA SCHOK kachiwiri m'gulu asidi mkombero tricarboxylic.

Choncho, molekyulu mmodzi wa shuga aumbike kwa 38 mamolekyulu wa ATP (awiri - chifukwa glycolysis anaerobic, asanu - chifukwa cha makutidwe ndi okosijeni wa mamolekyulu awiri nad · H + H +, amene anapanga pa oksireduktsii glycolytic ndi 30 - chifukwa TCA). CTLs dzuwa la 0.5. Ena a mphamvu ndi ankakhala moyo wotayirira monga kutentha. The TCA ali oxidized 16-33% lactate asidi, ena misa ali resynthesis wa glycogen.