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підручники. біохімія / Uchebnik_po_Biokhimii_E_S_Severin

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1-6).

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27

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Pa3phIB 6oJibllIOro KOJIHqecrna cJia6h1x CBJI3eti B MOJieKyJie 6eJIKa IIPHBOLJ:HT K Pa3PYIIIeHHIO ee HaTHBHOH KOHcl>opMauww. TaK KaK pa3phIB CBJI3eti !IOLI: )l,eHCTBHeM pa3JlHqHbIX ct>aKTOpOB HOCHT CJTy- '-lattHhJMxapaKTep, TO MOJieKyJihl 0)1.HOfO HHLJ:HBH)l.y-

aJihHOro 6eJIKa rrptto6pern10T B pacrnope ¢opMy CJiyqatiHO cct>opMMpOBaBWl1XC51 6ecrropJILJ:OqHbIX KJiy6KOB, orn.11qaIOIUHXC5l Ll:PYf OT LJ:pyra rpeXMepHOM CTPYKTypoM.. IlOTepJI HaTtt:BHOM. KoHcl>opMaUHH corrpOBO)!(LJ:aeTCJI yTpaTOti crreu.11ct>HqecKOM cPYHKUHH 6eJIKOB. 3TOT rrpouecc HOC.HT Ha3BaHHe LJ:eHaTypauHH 6eJIKOB. IlpH LJ:eHarypau1111 6eJIKOB He rrpOMCXO)l.HT pa3phIBa rreTITMLJ:HhIX CB513eti:, T.e. rrepBHqHaJI CTpYKTYPa 6eJIKa He HapYIIIaeTCJI.

B LJ:eHaryp.11poBaHHOM 6eJIKe rMLJ:poct>o6ttble paMKaJihI, KOTOPhie B HaTHBHOH CTP~ MOJieKYJihl cnpJITaHhI BHYTPH f.11)],pocl>o6Horo HLJ:pa, OKa3hIBaIOTCJI Ha ITOBepXHOCTH. Ilp.11 LJ:OCTaTOqHo BhICOKOH KOHuempauntt: 6eJIKa H OTCYTCTBHM CHJlbHOfO OTTaJTKHBa10iuero 3apMa MOJieKYJihI Moryr o6he.lJ,MIDIThC5l Ll:PYf c Ll:PYfOM fHLl:POcP06HhIMH B3aHMO)l.eHCTBltllMM, rrp11 3TOM pacrnopHMOCTb 6eJIKa CHH)J(aeTCJI H IIpOHCXOLJ:HT 06pa30Bam1e ocaLJ:Ka.

KoMrraKTttaJI, JIJIOTHM rrpocrpaHcTBeHHaH CTPYKrypa HaTHBHOfO 6eJIKa rrptt: LJ:eHarypaUHH pe3KO yBeJIWIHBaeTCJI B pa3Mepax H CTaHOBHTCJI JiefKO LJ:OCTYIIHOM LJ:JIJI paciuerrJieHHJI rrerrTHLJ:HhIX CBJI3eti rrpoTeoJI11T11qecK.11M.11 ct>epMemaMH (pttc. 1-14). TepMWieCKaJI o6pa60TKa MJICHOH ITHIUH rrepeLJ: ynorpe6JieHMeM He TOJihKO yJiyqIIIaeT ee BKYCOBbie Ka'-!eCTBa, HO H 06JieNaeT ee cl>epMeHTaTHBHOe nepeBap.HBaHHe B IIHIUeBapMTeJihHOti: c11cTeMe. KpoMe Toro, LJ:eHaTY- p.11pyIOIUHM LJ:eHCTBHeM Ha mnueBhie 6eJIKM o6JiaLJ:aeT 11 KHCJiaH cpeLJ:a )l(eJiyLJ:Ka, BhJ3hIBaIOIUaJI )l.eHaTYPaUHIO Tex 6eJIKOB, KOTOph1e He rro)l.BepraJIHCh

28

1-15).

rrpe.usapHTeJTbttotl TeMrrepaTypttotl: o6pa6oTKe, a TaIOKe oKa3brnaeT .uettaTypwpyIOw.ee JJ,etl:cTBHe Ha 6eJTKH MHKpoopraHH3MOB, rrorrasurnx B )l(eJTyJJ,OK c mm.1,etl:.

5. <PaKmopbt, 6bt3bt6a10w.ue iJeuamypau.u10

6e.t1K06

)l,ettaTypaumo 6eJTKOB Bbl3bIBaIOT q>aKTOpbI, cnoco6crnyIOW.He pa3pbIBY r1111,po¢06HbIX, BOJJ,Opo.u- HblX 11. 11.0HHblX CB513ett, CTa6HJTl13Mpy!OW,HX KOHQJOpMaUMIO 6eJTKOB:

BbICOKllil TeMnepaTypa (60JTee 50 °C), yseJTttllHBalOW,llil TeTIJIOBOe )J,BH)l(etttre aTOMOB B MOJTeKYJie H npHBOMW.llil K pa3pblBY CJTa6bIX CB513etl:;

HHTeHCMBHOe BCTpHXHBaHtte paCTBOpa, rrpM-

BO,llHW,ee K corrpHKOCHOBeHHIO 6eJIKOBbIX MOJieKYJT c 803)],yllIHOH cpeJJ,otl: Ha rrosepXHOCTH pa3JJ,eJia ¢a3 l1 H3MeHeHHIO KOHQJOpMaUMli 3THX MOJieKYJT;

oprattw1ecKtte sew.ecrna (ttarrpwMep, ::>TMJIOBhIH cmrpT, <)Jetton 11 era rrpomsoJJ,Hhie) cnoco6tthI B3aHMOJJ,etl:CTBOBaTb c QJYHKUllOHaJTbHblMH rpyrrrraMH 6eJIKOB, lffO rrpHBO)J,HT K HX KOHQJOpMaUllOHHblM H3MeHeHMHM. )],JTH JJ,eHarypauwtt 6eJTKOB B 6ttOXHMMl{eCKHX llCCJie)J,OBaHttHX qacTO llCTIOJlb3YIOT Moqestttty MJlH ryaHll)J,llHXJIOpH,ll, KOTOphre o6pa3YJOT BOLlOPOLlHbie CBH3H c aMHHO- H Kap60HHJlbHbIMH rpyrrrraMll rrerrT1111,HOro OCTOBa H HeKOTOph!MH QJYHKUHOHaJTbHbIMH rpyrrrraMM pa.uttKaJIOB aMttHOKllCJIOT. Tipowcxo-

LlHT pa3pbIB CBH3etl:, yqaCTBYJOW,HX B ¢opMMpOBaHHll BTopw1Hoi1: H TpeTttl{HOM CTPYKTYPhI HaTMBHhIX 6eJTKOB, H o6pa30BaHHe HOBbIX CBH3eti c XllMMlleCKHMH peareHTaMH;

0

NH

II

II

H2N-C-NH2

H2N-C-NHCI

Mo~ee111Ha

lyaHlllAlllHXnoplllA

KMCJIOTbl l1 W,eJIOllli, H3MeHHH pH cpeJJ,bI, Bbl3bJBaIOT rrepepacrrpeJJ,eJieHtte cB513eH B MOJieKyJTe 6eJTKa;

COJTH T51)1(eJTbIX MeTaJTJIOB (TaKtte KaK Me)J,h,

PTYTb, cepe6po, cs11.tteu H JJ,p.) o6pa3yIOT rrpoqHbre CBH3H c Ba)l(HbIMll QJYHKUHOHaJTbHblMH rpynnaMH 6e11Kos (qaw.e scero c -SH), tt3MeH5151 llX KOHQJOpMaUHIO H aKTHBHOCTh;

.ueTepreHTbI - sew.ecrna, coL1.ep)l(aw.11e m.upo- ¢o6HhIM yrnesoLI.opoLI.HhIH paLI.ttKM 11 mJJ,poQJHJihHYIO QJYHKUHOHaJibHYIO rpynrry (TaKHe sew.ecrna Ha3hIBaIOT aMQJHQJHJlbHhIMtt). fttnpo¢06ttb1e PMHKaJihI 6eJIKOB s1auMonei1crnyIOT c rl11l,po¢o6Hh1Mll qacrnMH )J,eTepreHTOB, LITO H3MeHHeT KOHQJOpMau11.10 6eJIKOB. )l,eHaTypnposaHHhIH ITO)], neHCTBHeM )J,eTepreHTOB 6eJTOK 06billHO OCTaeTCH B pacrnopeHHOM BH,lle, TaK KaK mJJ,pOQJllJibHble LiaCTll nettaTypttpy10-

ll1ero sew.ecrna ynep)l(lfsa10T ero s pacrnope.

K Hatt6oJiee H3BeCTHbJM )leTepreHTaM OTHOCHT pa3Jilll{HbJe MbIJia (pHC.

HarnBHblill 6enoK

PMc. 1-14. CTPYKTYP& H&TMBHOM Monei<ynb1 6enKa (e 1..1eHTpe) MTpex AeHaTypMpoeaHHblX MoneKyn aToro JKe 6enKa.

29

Han'IBHbl~ 6enoK

r11,QpOcp06HblMl1 y4aCTKaMl1 ,Q9TepreHT

 

np11coe,Q11H~eTc~ Kr11,Qpocpo6HblM pa,Q11KanaM

 

aM11HoK11cnoT non11nem11,QHO~ L1en11

PMc. 1-15. JleHa-rypa4MS1 6enKoe c nOMO~blO AeTepreHTOB.

 

6. MeiJuu,uncKue acneKmbl KonrjJopMau,uonnoii

.406ll.4bHOCmU 6f!.llK06

CKJIOHHOCTh 6oJThIIIMHCTBa 6eJTKOB K aettarypaUMM B rrpouecce ux BhILJ.enemrn, xpattemrn 11 11cITOJTh30Bamrn cepbe3HO 3aTpyLJ.mieT MX rro.rryqem1e M rrp11MeHeH11e B Me,UHUHHe.

,UJrn rrpaBl1JlhHOro o6paIIIeHlrn c 6eJIKOBhIMH JTeKapcrneHHbTMH rrperrapaTaMH K HMM rrpMKJia)lhTBaIOT HHCTPYKUMIO, B KOTopo:M YKa3hIBaJOT ycnoBHH nx xpaHeHM51 H 11crrOJih30BaHMH. TaK, 6oJihllIHHCTBO 6eJTKOBhIX rrperrapaTOB He06XO)J.HMO xpaHlffh B XOJIO)ll1JlhHHKe rrptt TeMnepaTYPe He BbTllle 10 °C, pacrnopHTh cyx11e npenapaThT oXJTa)l()J:eHHotl: ao

KOMHaTHOH TeMIIeparypbT KHITWieHOH BO)lOH BO J13-

6e)l(aHMe ux aettazypauMH.

7. IlpUMenenue iJenamypupy10lll,UX azenmoB

8 6uo.110w11ecKux uct:J1eiJ0Banu.ax u MeiJuu,une

B 6uoxHMM'lecKHxrrccnenoBaHM5IX rrepeLJ. onpenenem1eM B 6ttOJIOfH:qecKOM MaTepuaJie HM3KOMOJieKyJrnpHbIX coe)lMHeHMH M3 paCTBopa 06h1qHo YllaJIBIOT 6eJIKM. )1,M 3Toi1: uenu qame Bcero ucrroJih3yIOT TpMXJTOPYKCYCHyIO KHCJIOTy. CTocJie ee )lOfiaBJiemrn B paCTBOp ,UeHaTypHpOBaHHhie 6eJIKH Bhma,UaIOT B ocaaoK M nerKo Y.llaJIHIOTCH cpl1JlbTpoBattueM. TpuXJTopyKcycHyIO KHCJIOTy MO)l(HO TaK- )Ke MCIIOJ1h30BaTb )J.JTSI )leHarypaunu cpepMeHTOB B uemIX npeKpameHM51 <PepMeHTaTMBHOM peaKUMM.

B MeLJ.HUH:He )J.ettarypupy10mue areHThI qacrn ucIIOJTh3yIOT )lJlSI CTepl1JIM3aUMM Me)J.HUMHCKMX MHCTpyMeHTOB M MaTepuaJia, a TaK)l(e B KalJeCTBe aHTMcenTMKOB. HarrpuMep, B aBTOKJiaBax rrpu BhTCOKotl: TeMrreparype CTepMJIM3yIOT Me,!l,MUHHCKHe HHCTpyMeHTbl l1 MaTepMaJibI.

<l>eHOJI M ero rrpOM3BOllHbTe (KPe30JT, pe30PUMH) OTHOCITT K M3BeCTHhlM aHTMceITTMKaM apoMaTMlJeC-

KOro pSl)la. 06JTa)J.aIOIIIHe BbICOKOM fMllPO¢l06HOCTbIO, OHH 3cpcpeKTHBHO )J.eHCTBYIOT Ha BereTaTHBHbie cpopMhT 6aKTeputf u rprr6h1, Bbl3h1Ba5l nettazypaumo HX 6eJIKOB. 3Q:JQ:ieKTI1BHOCTh aHTMCeTITHlJeCKMX cBotfcrn YMeHbUiaeTCH c yBeJI11Y:em1eM paCTBOpMMOCTH npenaparn B BOLJ.e.

OOH

OH

HOOOH

0

I

~'

 

 

 

CH3

 

<l>etton

Kpe3on Pe30PL\11H

Pacrnop Kpe3oJTa B KanutrttoM Mhrne H3BecTeH KaK nperrapaT JIH30JT, np11Mem1eMhIM B Ka'lecrne ,Ue311HQ:i11u11pyromero cpeLJ.crna.

Bepe30Bh1tt LJ.erOTh - OLJ.Ha H3 octt0Bttb1x cocrnBtth1x qacTet'rMa311 BttlllHeBcKoro, COLJ.ep)!(HT B CBOeM COCTaBe Q:ieHOJT. CTperrapaT, HCI10Jlh3yeMbltt

Ll.J15l neqeHH5I paH, o6naaaeT BbICOKHM aHTHMHKpo6HblM )J.eHCTBHeM.

3Ha'-!HTeJTbHOeKOJIHlJeCTBO aHTMCeITTHKOB npe,!!,- CTaBJieHO COAAMH TH)l(eJihIX MeTaJIJIOB. llx aHTHMl1Kp06H6e )J.ettCTBMe CB5I3aHO c TeM, lJTO ~e B )J,OBOJlbHO HM3KHX KOHUeHTpal.l,HSIX OHM B3aHMO- ,!l,ettcTByKn c 6eJTKaMM MHKpoopraHH3MOB, 6JIOKHpyIOT HX SH-rpynrrhI H H3MCH51TOT rrx KOHQ:lopMaUHIO. 1'fa-3aBhlCOKOM TOKCff'IHOCTH'OOJlhllIHHCTBO JieKapcTB, CO)l,ep)l(aIIIHX COJIH TH)l(eJihIX MeTaJIJIOB, np11MeH5IIOT B KalJecrne IIOBepXHOCTHhIX aHTHCenTHKOB.

TaK, BhICOKo:H aHTHMHKP06Hoif aKTHBHOCThIO 06Jia,!l,aeT cyJTeMa - llHXJTOPH.ll PTYTH (HgCl 2). Ee 11crroJTh3YIOT .llJlSI o6pa6oTKH PYK H lle311ttcpeKUHH rroMeIUeHHtl:. C.rryqa:Httoe HJIH npeLJ.HaMepettttoe OT-

30

paBJiem1e rrperraparnMH PTYTlf BhI3hIBaeT TIDKeJJhie HeKpOTJflleCKMe rropa)l(eHlf51 CJJM3MCTOM o6oJioqKM nnw:eBapwTeJTbHoro TPaKrn M HeKPoTwqecKMe 111MeHeHlf5I B rroqKax. AHTMMllKpo6HhIMlf cBortcrnaMlf o6Jia,n.aIOT 11 rrperrapaThI cepe6pa, TaKHe KaK mnmc

(AgN03), KOMaproJI (cepe6po KOJIJJOH)J,aJJbHOe), rrpMMeIDieMble )J..JUI o6pa60TKM CJIM3MCThIX o6oJIO'feKrrpw wmpeKll,lfOHHhIX 3a6oneBamrnx.

B Jl,aHHhiit CTPYKTYPHhIH MOTHB BXOMT Jl,Be a- crrttpaJI11: OJl,Ha 6oJiee KopoTKaH, Jl,pyraH 6oJTee JJ,JIHHHM, KOTOPbie coe)J,HHeHbl IIOBOPOTOM IIOJil1rrerrTM,llHOH uem1. ooJiee KOpOTKaH cx-crrtt:panh pacrroJiaraeTCH norrepeK 6opo3JJ,KM, a 6oJiee MHHHM <X-CITMpaJTb - B 60JiblllOM 6op03Jl,Ke, o6pa3yH HeKOBaJTeHTHbie crre1111¢H'feCKMe CB513H pa.n.tt:KaJTOB aMMHOKMCJIOT c HYKJieOTMJl,aMtt )],HK (ptt:c. 1-17).

r. CYilEPBToPHqHAfl cTPYKTYPA BEJIKos

IlpoCTpaHCTBeHHaH CTpYKTypa K<DK,11,0fO 6eJIKa MH,11,MBH)J.YaJihHa M orrpeJJ,eJTHeTCH ero rrepBM'-IHOM cTpyKTyport. OJJ,ttaKo cpaBHem1e KoH¢opMau11rt pa3HhIX rro CTPYKTYPe M ¢YHKU1f51M 6eJTKOB BhrnBlfJTO HaJIMqMe y HMX rroxm1mx CO'feTaHMM3JieMeHTOB BTOpMqHort CTPYKTYPhI. TaKort crreuMcPM'fecKMM rropmi;oK ¢opMMposaHmr BTopM'-IHhIXCTPYKTYP Ha3bIBaIOT cyrrepsmpM'-IHOM CTPYKTyport 6eJIKOB. CynepsmpM'-IHMCTPYKTYPa ¢opMwpyeTrn 1a c'ffa Me)J(pa,D.MKaJihHhIX B3aMMOJl,eMCTBMM.

OrrpeJl,eJieHHhie xapaKTepHhie co'feTaHMHa-crrw- panert 11 ~-CTPYKTYP qacTO o603Ha'faIOTKaK «CTpyKTYPHhie MOTMBhl». OHM lfMeIOT crreuMcPM'fecKMe Ha3BaHMH: «<X-CITMpaJib-ITOBOpoT-a-crrwpaJih»' «CTPYKTYPa ~-60'-IOHKa», «JieMUMHOBaH 3acTe)J(KaMOJIHlf5I», «UMHKOBhitt rraJieu» 11 Jl,p. Crreu11¢w1ecKoe rrpocTpaHcrneHHoe pacrroJIO)l(eH11e a-crrttpanert

If ~-CTpYKTYP ¢opMttpyeTCH 3a cqfa Me)l(pa,D.MKaJih-

HbIX B3aMMOJl,eMCTBMM.

I. CynepBmopu11nan cmpyKmypa muna f3-6011on1Ca

TaKai:r CTPYKTYPa Jl,ertcrn1ueJihHO ttarroM11ttaeT 60'-IOHOK, rJl,e K<DK,11,aH ~-CTpyKTypa ( o603Ha'feHHaH Ha pwc. 1-16 CTpeJIKOM) pacrrOJIO)[(eHa BHYTPM If CBH3aHa c CX-CITMpaJTbHhIM yqacTKOM ITOJil1rrenTMJl,HOM uerrM, HaXOJl,Hlll,lfMCH Ha ITOBepxHOCTM

MOJieKYJihl.

CynepsmpM'-IHYIOCTPYKTYPY B BMJl.e ~-6oqottKa

11MeIOT HeKOTOphie ¢epMeHThl, HarrpMMep TpM030- ¢oc¢aTM30Mepa3a M omrn noMeH rrtt:pysaTKMHa3hI

(pHC. 1-16).

2. CmpyKmypHbtU MomuB «a-cnupatlb- noBopom-a-cnupllJlb»

3. CynepBmopu11naa cmpy«mypa B Bude «~UHKOBozo nllJlb~a»

3ToT BM,!l, cyrrepBTOptt'-IHOM CTPYKTYPhI TaK)l(e 'faCTO OTMe'faIOT B )lHK-CB513bIBaIOW:MX 6eJTKax. «U11HKOBhIH rraneu» - ¢parMeHT 6eJTKa, COJl,ep- )l(aw:11rt OKOJIO 20 aMlfHOKMCJIOTHbIX OCTaTKOB, B KOTOpOM aTOM UlfHKa CBH3aH c pa,D.11KaJiaM11 qeTblpex aMMHOKMCJTOT: 06bl'-IHO c Jl,BYMH OCTaTKaMM

A

5

Ptic. 1-16. CynepeTopt1'1Ha11cTpyKTypa e eti,qe [3-6o'!OHKa. A - Tpt103ocj>occj>aTM30Mepa3a; 6 - ,qoMeH ntipyeaTKMHS3br.

Asoi1Hasi

cn111panbAHK

2 a-cn111pan1-1

AHK-cssiab1Baiow,ero

6enKa

3TOT «CTpYJ<TYpHbltl MOTMB» o6ttapJ')KeHBO MHOrnx Ll,HK-CBH3bIBaIOW:HX 6eJIKax. Ll,Byxcrrtt:paJTbHaH CTpYKTYPa .UHK MMeeT Jl,Be 6op03Jl,KM - 60JihlllYI0 11 MaJIYIO. BoJihlllaH 6opo3JJ,Ka xopolllo rrpttcrroco6JieHa )J..JUI CBH3bIBaHl151 6eJIKOB, MMeIOW:11X He60JihIllHe CTIHpaJTbHhie yqacTKM.

Ptic. 1-17. Ce11ab1eaHt1e cynepBTOplll'IHOMCTPYKTYPbl «a-cnt1- panb-noeopoT-a-cnt1panb» ,QHK-ce11ab1eaio~ero 6enKa e 6onbWOM 6opo3,qKe llHK.

31

1-19).
1-18).

UHCTe1rna H nsyw1 - rHCTHJJ.HHa. B HeKoTOPhIX CJiy1rn5!X BMeCTO OCTaTKOB rHCTH,llHHa TaIOKe HaxOLl5lTC5l OCTaTKH UHCTeHHa (pHC.

D.sa 6Jil13KO JieX<fillUlX OCTaTKa U11CTeHHa OTJJ,eJieHbJ OT LlByx JJ.PYfMX OCTaTKOB rncTH,llHHa (l1.lll1 UHCTeHHa) aMl1HOKHCJIOTHOM TIOCJieJJ,OBaTeJibHOCTbIO, COCTOmuei1 rrpHMepHO H3 12 aMHHOKH:CJIOTHbIX OCTaTKOB. 3ToT yqacTOK 6eJIKa o6pa3yeT CX-CffiipaJib, KOTOpa5! MO)J(eT cneum:Pwrno CB5!3bIBaTbC5! c perynmopHbIMH Y'IaCTKaM11 6011hllIOi1 6opo3,LI.KH D.HK. CrreumplfllHOCTh'B3a11MO,LI.eHCTBH5! ll,HK-CB5!3bIBaIOil(ero 6eJTKa c orrpeneneHHoti: o6nacThIO ll,HK 3as:11cHT OT rrocneLlOBaTeJThHOCTH aMMHOKH:CJIOTHbIX OCTaTKOB, pacrroJIO)J(eHHbIX B o6JiaCTM «UMHKOBOro IlMbUa>>.

JlettUHHOBbie OCTaTKM a-cnHpaJTH 0,llHOfO 6eJIKa MOryT B3aHMOJJ,eti:CTBOBaTh c JieHUHHOBbIMl1 OCTaTKaMH JJ,pyroro 6eJTKa C ITOMOlUbIO rHJJ.POcPOfiHblX B3aHMO,LI.eti:crnHtl:, coe,amurn HX BMecTe (p11c.

I1p11MepoM coe,llHHeHH.51 6eJIKOB c IlOMOlUbIO «JieMUHHOBOH 3aCTe)l(l(H-MOJIHHH» MOryT CJIY)i(lfTb fHCTOHhl. fHCTOHbl - 5!JJ,epHhie 6eJIKM, B COCTaB KOTOphIX BXO,llHT 60JihlllOe KOJIH'leCTBO IlOJIO)J(J1TeJihHO 3apIDKeHHblX aMHHOKMCJIOT - aprHHHHa 11 JIH3HHa. MoneKyJibI r11cTOHOB o6ne,nHH5!IOTC5! B KOMITJieKCbl, COCT05lll(He H3 8 MOHOMepHblX 6eJIKOB c IlOMOlUbIO «JieHUHHOBblX 3aCTe)J(eK», HeCMOTp5! Ha TO, 'ITOBee MOHOMepbl MMeIOT Cl1JlhHblH rroJIO)J(MTeJibHblH 3ap5!JJ,.

4. Cynepomopu11uaa cmpy«mypa

8 ouiJe «AeiiU,UH080U JacmeJICKU-MOJlHUU»

HeKOTophie ll,HK-CB5!3bIBaIOm11e 6eJIKM OJIHroMepHhI, T.e. CO,LI.ep)J(aT B CBOeM COCTaBe HeCKOJibKO rronwnerrTH,llHhTX uenetl:. KpoMe Toro, cymeCTBYIOT 6eJIKH:, KOTOPhie cPYHKUHOHllPYIOT B KOMTIJieKce c apyrnMH 6eJIKaMl1.. 06beJJ,HHeHHe rrpOTOMepoB MJIH OTJJ,eJihHbIX 6eJIKOB B KOMITJieKCbl HHOfJJ.a ocymeCTBJUieTC5! c TIOMOlllbIO CTpYKTYPHhlX MOTHBOB, Ha3bIBaeMhIX «JieHUHHOBa5! 3aCTe)l(I(a-MOJIHH5!».

Ha rrosepxHOCTH Ka)J(Lloti: H3 JJ.Byx B3aHMO,llei1CTBYIOlllHX ITOJTHITeIITH,llHhIX uerre:H HJIH 6eJIKOB HMeeTC5! a-CilHPaJThHblll yqaCTOK, conep)J(alUHM no Kpai1Hei1 Mepe 4 OCTaTKa JTeHUHHa. Jleti:UHHOBbie OCTaTKM pacrroJiaraIOTC}[ qepe3 Ka)J(Llble 6 aMHHOKHCJTOT OJJ,HH OT ,llpyroro. TaK KaK KmKJJ,bJH BHTOK a-cmfpaJTH co.nep)J(HT 3,6 aMHHOKMCJIOTHbIX OCTaTKa, pa)lHKaJTbl JieHUHHa HaXOMTC}[ Ha nosepXHOCTH Kff)K,IJ,Oro BTOporo BHTKa.

,I(. ,I(OMEHHAH CTPYKTYPA BEJIKOB

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