I-D-mannose ne-L-mannose ama-enantiomers afanayo, futhi umehluko wawo obalulekile usekumisweni kwawo okuhlukile kwendawo, okuholela emisebenzini nemisebenzi yebhayoloji ehluke kakhulu. Okulandelayo amaphuzu ayinhloko ahlukanisayo:

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1. Umehluko oyisisekelo ekwakhekeni kwamakhemikhali

Amaphuzu ajwayelekile:

Ifomula yamangqamuzana ithi C ? H ?? O ?, okuyi-C-2 isoma yeglucose (okungukuthi i-hydroxyl (- OH) isiqondiso kukhabhoni yesibili iphambene neglucose).

Umehluko Obalulekile:

Indlela yokulebula ye-D/L isuselwe kusistimu yereferensi ye-glyceraldehyde:

I-D-Mannose: Isiqondiso se-hydroxyl (- OH) sekhabhoni enenombolo ephezulu ye-chiral (C5) ku-molecule iqondaniswe ne-D-glyceraldehyde (etholakala ngakwesokudla ku-Fischer projection).

I-L-mannose: I-hydroxyl direction ye-C5 ihambisana naleyo ye-L-glyceraldehyde (etholakala ohlangothini lwesobunxele ku-Fischer projection).

Zombili ziyizithombe zesibuko zodwa futhi azikwazi ukudlulana. .

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I-Fischer projection equation: ukuqhathanisa kwesakhiwo phakathi kwe-D-mannose (kwesokunxele) kanye ne-L-mannose (kwesokudla)

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2. Umsebenzi webhayoloji kanye nomehluko we-metabolic

Izici D-mannose L-mannose

Ubukhona Bemvelo ? Bukhona kakhulu emvelweni (ezithelweni, ezitshalweni, kuma-glycoprotein) ? Akukhona ngokwemvelo (ukwenziwa kwelabhorethri)

Umsebenzi webhayoloji ? Unomsebenzi obalulekile wezinto eziphilayo ?? Awukho umsebenzi owaziwayo webhayoloji (awukwazi ukuguqulwa futhi usetshenziswe umzimba womuntu)

Indlela ye-metabolic ingaba yi-phosphorylated yi-mannose kinase (MK) futhi ayikwazi ukubonwa ngama-enzymes we-metabolic womuntu (ama-enzyme ane-chiral ethize)

Imisebenzi ye-physiological ihlanganisa ukuhlanganiswa kwe-glycoprotein, ukuvimbela i-UTI, ukwelashwa kwe-CDG, njll

Cishe awukho umthelela kushukela wegazi (ngenxa yokungamuncwa/ukwenziwa kwe-metabolism)

Kungani uhlobo lwe-D kuwukuphela kwefomu elisebenza ngokwebhayoloji? .

Ama-Enzyme nabathuthi entweni ephilayo banokucaciswa kwe-chiral okuqinile (i-stereoselectivity):

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Ukuqashelwa kwe-enzyme ye-Metabolic:

I-mannose kinase (MK) esibindini somuntu ibona futhi i-phosphorylates i-D-mannose kuphela futhi ayikwazi ukusebenza ku-L-isomer.

Imininingwane ye-Transporter:

Izithuthi zeglucose zamathumbu (ezifana ne-GLUT5) zikhetha ukuthutha i-D-mannose (nakuba isebenza kahle kakhulu), kuyilapho i-L-mannose ayikwazi ukumuncwa ngempumelelo.

Ukubophezela kwe-receptor:

Okuqondiwe okufana ne-mannose receptor (MRC1) nama-adhesin e-FimH ebhaktheriya abophezela ngokukhethekile ku-D-mannose noma okuphuma kuyo (okufana ne-D-mannoside).

4. Ukusetshenziswa okungenzeka kwe-L-mannose

Nakuba ingenawo umsebenzi webhayoloji, i-L-mannose inenani elithile ocwaningweni lwesayensi nasembonini

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Ucwaningo lwe-Biochemical:

Njengenkomba ye-D-mannose, isetshenziselwa ukutadisha indlela yokuqaphela i-chiral yama-enzyme.

Chemical synthesis intermediates:

Isetshenziselwa ukukhiqiza ushukela ongavamile noma ama-molecule ezidakamizwa ezi-chiral.

Idizayini yokuvimbela:

Ingase isebenze njengesivimbeli sokuncintisana sama-enzyme athile (adinga ukuqinisekiswa okuhlosiwe).

Izinto ezibalulekile:

Isetshenziselwa ukulungisa ama-chiral polymers noma ama-nanomaterials (njengezinzwa ze-chiral).

Isifinyezo Esiyinhloko

Ubukhulu bokuqhathanisa i-D-mannose L-mannose

Ingqikithi yamakhemikhali yama-isomer esandla sokudla akhona emvelweni, ama-isomer angakwesokunxele ahlanganiswe ngokuzenzakalelayo

I-Biological metabolism ? Ingenziwa i-metabolized ngama-enzymes womuntu ? Angeke ibonwe ama-enzyme womuntu

I-Physiological function glycosylation, anti infection, ukwelashwa kwezifo ezingavamile akukho

Umuthi onenani elisetshenziswayo (ukuvimbela i-UTI, ukwelashwa kwe-CDG), ama-reagents ocwaningo lwesithasiselo sokudla, ama-chemical synthesis intermediates

Umthamo omkhulu ungase ubangele isifo sohudo (kodwa kuphephile ngokuphelele), okungewona ubuthi kodwa akutholakali nge-bioavailable

Inkumbulo elula:

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I-D-type="uhlobo olusebenzayo lwebhayoloji": ikhona ngokwemvelo, ingenziwa imetabolism, futhi inezinhlelo zokusebenza ezingokoqobo.

L-type="uhlobo lokulawula isibuko": enziwe ngokuzenzakalelayo, ngaphandle komsebenzi webhayoloji, isetshenziselwa ucwaningo lwesayensi noma ubunjiniyela bamakhemikhali.

Igama elithi 'mannose' elishiwo emkhakheni wezokwelapha nokudla okunomsoco libhekisela ku-D-mannose. I-L-mannose ayinalo inani lesicelo somtholampilo, kodwa njengethuluzi lamakhemikhali, inamandla athile ocwaningo lwesayensi.