D-mannose da L-mannose su ne eantiomers wa?anda ke madubi juna, kuma mahimmancin bambancinsu ya ta'allaka ne a cikin bambance-bambancen yanayin yanayin su, yana haifar da ayyuka da ayyuka na rayuwa daban-daban. Wadannan su ne mahimman abubuwan da ake rarrabewa:

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1. Asalin bambance-bambance a cikin tsarin sinadarai

Abubuwan gama gari:

Tsarin kwayoyin halitta shine C ? H ?? O ?, wanda shine C-2 isomer na glucose (watau hanyar hydroxyl (- OH) akan carbon na biyu ya saba da glucose).

Babban Bambance-bambance:

Hanyar lakabin D/L ta dogara ne akan tsarin tunani na glyceraldehyde:

D-Mannose: Hanyar hydroxyl (- OH) na mafi girman ?ididdiga na carbon chiral (C5) a cikin kwayoyin halitta yana daidaitawa da D-glyceraldehyde (wanda yake a gefen dama a cikin tsinkayar Fischer).

L-mannose: Hanyar hydroxyl na C5 ya dace da na L-glyceraldehyde (wanda yake a gefen hagu a cikin tsinkayar Fischer).

Biyu hotunan madubi ne na juna kuma ba za su iya ha?uwa ba. "

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Matsakaicin tsinkayar Fischer: kwatancen tsari tsakanin D-mannose (hagu) da L-mannose (dama)

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2. Ayyukan Halittu da bambance-bambancen rayuwa

Halaye D-mannose L-mannose

Kasancewar Halitta ? Yadu a cikin yanayi (a cikin 'ya'yan itatuwa, tsire-tsire, glycoproteins)

Ayyukan Halittu ? Yana da mahimman ayyukan ilimin halitta

Hanyar rayuwa na iya zama phosphorylated ta mannose kinase (MK) kuma ba za a iya gane shi ta hanyar enzymes na rayuwa na ?an adam ba (enzymes suna da takamaiman chiral)

Ayyukan physiological sun ha?a da ha?in glycoprotein, rigakafin UTI, maganin CDG, da dai sauransu

Kusan babu wani tasiri akan sukarin jini (saboda rashin shayarwa / metabolized)

Me yasa nau'in D-nau'in shine kawai nau'i mai aiki na halitta? "

Enzymes da masu jigilar kayayyaki a cikin rayayyun halittu suna da takamaiman takamaiman chiral (stereoselectivity):

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Ganewar enzyme Metabolic:

Mannose kinase (MK) a cikin hanta ?an adam kawai ya gane kuma phosphorylates D-mannose kuma ba zai iya aiki akan L-isomer ba.

?ayyadaddun kayan sufuri:

Masu jigilar glucose na hanji (kamar GLUT5) sun fi son jigilar D-mannose (ko da yake yana da ?arancin inganci), yayin da L-mannose ba zai iya ?aukar shi yadda ya kamata ba.

Daure mai kar?a:

Manufa irin su mai kar?ar mannose (MRC1) da ?wayoyin cuta na FimH adhesins suna ?aure musamman ga D-mannose ko abubuwan da suka samo asali (kamar D-mannoside).

4. Yiwuwar amfani da L-mannose

Kodayake rashin aikin ilimin halitta, L-mannose yana da takamaiman ?ima a cikin binciken kimiyya da masana'antu

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Binciken Biochemical:

A matsayin abin tunani don D-mannose, ana amfani da shi don nazarin tsarin gane chiral na enzymes.

Tsakanin ha?akar sinadarai:

An yi amfani da shi don ha?a sukarin da ba kasafai ba ko ?wayoyin magungunan chiral.

Tsarin hanawa:

Maiyuwa yayi aiki azaman mai hanawa gasa don takamaiman enzymes (yana bu?atar tabbatar da niyya).

Kayayyaki na musamman:

Ana amfani da shi don shirya polymers na chiral ko nanomaterials (kamar firikwensin chiral).

Takaitacciyar Ma?alli

Girman kwatanta D-mannose L-mannose

Ma'anar sinadarai na isomers na hannun dama wa?anda ke wanzu a cikin yanayi, masu ha?ar isomers na hagu na wucin gadi.

Metabolism na Halittu ? Ana iya daidaita shi ta hanyar enzymes na ?an adam

Ayyukan Physiological glycosylation, rigakafin kamuwa da cuta, maganin cututtukan da ba kasafai ba

Maganin ?imar da aka yi amfani da shi (Rigakafin UTI, jiyya na CDG), masu ha?aka binciken ?arin abinci mai gina jiki, tsaka-tsakin ha?in sinadarai

Babban kashi na iya haifar da gudawa (amma gaba?aya mai lafiya), mara guba amma ba ya wanzu

?wa?walwar ?wa?walwa mai sau?i:

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D-type = "nau'in aiki na halitta": yana wanzuwa a yanayi, ana iya daidaita shi, kuma yana da aikace-aikace masu amfani.

L-type = "nau'in sarrafa madubi": wanda aka ha?a ta hanyar wucin gadi, ba tare da aikin ilimin halitta ba, ana amfani dashi kawai don binciken kimiyya ko injiniyan sinadarai.

Kalmar 'mannose' da aka ambata a fagen magani da abinci mai gina jiki tana nufin D-mannose. L-mannose ba shi da ?imar aikace-aikacen asibiti, amma a matsayin kayan aikin sinadarai, yana da wasu yuwuwar binciken kimiyya.