Chefo ea noha e na le li-enzyme tse etsang hydrolyze carboxyl ester bond.Li-substrates tsa hydrolysis ke phospholipids, acetylcholine le acetate e nkhang hamonate.Li-enzyme tsena li kenyelletsa mefuta e meraro: phospholipase, acetylcholinesterase le esterase e nkhang hamonate.Arginine esterase e chefo ea noha e ka boela ea hlahisa arginine ea maiketsetso kapa lysine ka hydrolyze, empa haholo-holo e hlahisa li-protein peptide bond ka tlhaho, kahoo ke ea protease.Li-enzyme tse boletsoeng mona li sebetsa feela ho li-ester substrates 'me ha li khone ho sebetsa ho tlamahano efe kapa efe ea peptide.Har'a li-enzyme tsena, mesebetsi ea likokoana-hloko ea acetylcholinesterase le phospholipase e bohlokoa haholo 'me e ithutile ka botlalo.Mahloko a mang a noha a na le ts'ebetso e matla ea esterase e nkhang hamonate, e ka etsang hydrolyze p-nitrophenyl ethyl ester, a - kapa P-naphthalene acetate le indole ethyl ester.Ho ntse ho sa tsejoe hore na ts'ebetso ena e hlahisoa ke enzyme e ikemetseng kapa litlamorao tse tsebahalang tsa carboxylesterase, ho sa bue letho ka bohlokoa ba eona ba tlhaho.Ha chefo ea Agkistrodon halys Japonicus e ne e etsoa ka p-nitrophenyl ethyl ester le indole ethyl ester, li-hydrolysates tsa p-nitrophenol le indole phenol ha lia ka tsa fumanoa;Ho e-na le hoo, haeba li-ester tsena li itšoara ka chefo ea noha ea mofuta oa cobra Zhoushan le chefo ea noha ea Bungarus multicinctus, li tla tlosoa ka potlako hydrolyzed.Hoa tsebahala hore mahloko ana a cobra a na le ts'ebetso e matla ea cholinesterase, e ka 'nang ea ikarabella bakeng sa hydrolysis ea li-substrates tse ka holimo.Ha e le hantle, Mclean et al.(1971) e tlaleha hore chefo e ngata ea noha ea lelapa la Cobra e ka hydrolyze indole ethyl ester, naphthalene ethyl ester le butyl naphthalene ester.Mahloko ana a noha a tsoa: cobra, cobra e molala o motšo, cobra e ntšo, cobra ea khauta, cobra ea Egepeta, king cobra, golden cobra mamba, black mamba le white lipped mamba (D. aw o ntse a tseba eastern rhombola rattlesnake).
Chefo ea noha e ka hydrolyze methyl indole ethyl ester, e leng karoloana ea ho tseba tšebetso ea cholinesterase ka har'a serum, empa chefo ena ea noha ha e bontše tšebetso ea cholinesterase.Sena se bontša hore ho na le esterase e sa tsejoeng ea chefo ea cobra, e fapaneng le cholinesterase.Ho utloisisa mofuta oa enzyme ena, ho hlokahala mosebetsi o eketsehileng oa karohano.
1, Phospholipase A2
(I) Kakaretso
Phospholipase ke enzyme e ka etsang hydrolyze glyceryl phosphate.Ho na le mefuta e 5 ea phospholipase ka tlhaho, e leng phospholipase A2 le phospholipase.
A. , phospholipase B, phospholipase C le phospholipase D. Chefo ea noha haholo-holo e na le phospholipase A2 (PLA2), chefo e 'maloa ea noha e na le phospholipase B, le li-phospholipase tse ling li fumanoa haholo-holo liphatseng tsa liphoofolo le libaktheria.Setšoantšo sa 3-11-4 se bontša sebaka sa liketso tsa phospholipase tsena ho substrate hydrolysis.
Har'a li-phospholipases, PLA2 e ithutoe haholoanyane.E ka 'na eaba ke enzyme e ithutoang ka ho fetisisa mahlokong a noha.Substrate ea eona ke tlamo ea ester sebakeng sa bobeli sa Sn-3-glycerophosphate.Enzyme ena e fumaneha haholo mahlokong a noha, mahlokong a linotši, mahlokong a phepheng le liseleng tsa liphoofolo, 'me PLA2 e fumaneha ka bongata mahloko a linoha a malapa a mane.Hobane enzyme ena e pshatla lisele tse khubelu tsa mali 'me e baka hemolysis, e boetse e bitsoa "hemolysin".Batho ba bang ba boetse ba bitsa PLA2 hemolytic lecithinase.
Ludeeke o fumane pele hore chefo ea noha e ka hlahisa motsoako oa hemolytic ka ho sebetsa ho lecithin ka li-enzyme.Hamorao, Delezenne et al.e bontšitse hore ha chefo ea cobra e sebetsa ho serum ea pere kapa yolk, e etsa ntho ea hemolytic.Hona joale hoa tsebahala hore PLA2 e ka sebetsa ka ho toba ho phospholipids ea lera la erythrocyte, ea senya sebopeho sa lera la erythrocyte le ho baka hemolysis e tobileng;E ka boela ea sebetsa ho serum kapa lecithin e ekelitsoeng ho hlahisa lecithin ea hemolytic, e sebetsang liseleng tse khubelu tsa mali ho hlahisa hemolysis e sa tobang.Leha PLA2 e le ngata malapeng a mane a mahloko a noha, litaba tsa li-enzyme tse chefong tse fapaneng tsa linoha li fapane hanyane.Rattlesnake (C
Chefo ea noha e bonts'itse ts'ebetso e fokolang ea PLA2 feela.Letlapa la 3-11-11 le bonts'a papiso ea ts'ebetso ea PLA2 ea chefo e kholo ea 10 ea linoha tse chefo Chaena.
Letlapa la 3-11-11 Papiso ea mesebetsi ea phospholipase VIII ea chefo ea 10 ea noha Chaena
Bohloko ba noha
Ho lokolla mafura
Aliphatic acid,
Cjumol/mg)
Ts'ebetso ea hemolytic CHU50/^ g * ml)
Bohloko ba noha
Hlakola li-acid tse mafura
(^raol/mg)
Ts'ebetso ea Hemolytic "(HU50/ftg * 1111)
Najanaja atra
9. 62
leshome le motso o mong
Micracephal ophis
lintlha tse hlano ntlha e le 'ngoe lefela
kalyspallas
8. 68
likete tse peli le makholo a robeli
gracilis
V, acutus
7. 56
* * #
Ofiophagus Anna
tse tharo ntlha tse robedi pedi
lekholo le mashome a mane
Bnugarus fasctus
7,56
makholo a mabeli le mashome a robeli
B. multicinctus
ntlha e le nngwe robong tshelela
makholo a mabeli le mashome a robeli
Viper le russelli
supa ntlha zero tharo
T, mucrosquamatus
ntlha e le nngwe robedi tlhano
Siamensis
T. stejnegeri
0.97
(2) Karohano le tlhoekiso
Litaba tsa PLA2 ka chefo ea noha li kholo, 'me li tsitsitse ho futhumatsa, acid, alkali le denaturant, e le hore ho be bonolo ho hloekisa le ho arola PLA2.Mokhoa o tloaelehileng ke ho qala ho hloekisa gel holim'a mahloko a tala, ebe o etsa chromatography ea ion, 'me mohato o latelang o ka phetoa.Hoa lokela ho hlokomeloa hore ho omisoa ha leqhoa la PLA2 ka mor'a chromatography ea ion-exchange ha hoa lokela ho baka ho kopanya, hobane mokhoa oa ho omisa ka leqhoa o atisa ho eketsa matla a ionic tsamaisong, e leng ntho ea bohlokoa e bakang ho bokellana ha PLA2.Ntle le mekhoa e akaretsang e boletsoeng ka holimo, ho boetse ho amohetsoe mekhoa e latelang: ① Wells et al.② Analogue ea substrate ea PLA2 e ne e sebelisoa e le ligand bakeng sa affinity chromatography.Ligand ena e ka tlama ho PLA2 ka mahloko a noha ka Ca2+.EDTA hangata e sebelisoa e le tsebo.Ka mor'a hore Ca2 + e tlosoe, kamano pakeng tsa PLA2 le ligand e fokotseha, 'me e ka aroloa ho ligand.Ba bang ba sebelisa 30% ea organic solution kapa 6mol/L urea e le mokhoa oa ho tseba.③ Hydrophobic chromatography e entsoe ka PheiiylSephar0SeCL-4B ho tlosa trace PLA2 ho cardiotoxin.④ Anti-PLA2 antibody e sebelisitsoe e le ligand ho etsa affinity chromatography ho PLA2.
Ho fihlela joale, palo e kholo ea mahloko a noha PLAZ e se e hloekisitsoe.Tu et al.(1977) e thathamisitse PLA2 e hloekisitsoeng ho tloha chefong ea noha pele ho 1975. Lilemong tsa morao tjena, palo e kholo ea lihlooho tse buang ka karohano le tlhoekiso ea PLA2 e tlalehiloe selemo se seng le se seng.Mona, re shebana le karohano le tlhoekiso ea PLA ke litsebi tsa Machaena.
Chen Yuancong et al.(1981) e arotse mefuta e meraro ea PLA2 ho tloha chefo ea Agkistrodon halys Pallas e Zhejiang, e ka aroloa ka acidic, neutral le alkaline PLA2 ho ea ka lintlha tsa bona tsa isoelectric.Ho latela chefo ea eona, PLA2 e sa nke lehlakore e chefo ho feta, e fumanoeng e le presynaptic neurotoxin Agkistrodotoxin.Alkaline PLA2 ha e na chefo e nyane, 'me acidic PLA2 ha e na chefo e batlang e se na chefo.Wu Xiangfu et al.(1984) bapisa litšobotsi tsa PLA2 tse tharo, ho kenyelletsa boima ba limolek'hule, sebopeho sa amino acid, N-terminal, isoelectric point, thermal stability, mosebetsi oa enzyme, chefo le mosebetsi oa hemolytic.Liphello li bontšitse hore li ne li e-na le boima bo tšoanang ba limolek'hule le botsitso ba mocheso, empa li na le phapang e khōlō likarolong tse ling.Karolong ea ts'ebetso ea enzyme, ts'ebetso ea enzyme ea acid e ne e phahame ho feta ts'ebetso ea enzyme ea alkaline;Phello ea hemolytic ea enzyme ea alkaline liseleng tse khubelu tsa mali e ne e le matla ka ho fetesisa, e lateloe ke enzyme e sa nke lehlakore, 'me asiti e ne e sa tsoa mali.Ka hona, ho nahanoa hore phello ea hemolytic ea PLAZ e amana le tefiso ea molek'hule ea PLA2.Zhang Jingkang et al.(1981) ba entse likristale tsa Agkistrodotoxin.Tu Guangliang et al.(1983) e tlalehile hore PLA e chefo e nang le ntlha ea isoelectric ea 7. 6 e ne e arohane le ho hloekisoa ho tloha chefo ea Vipera rotundus ho tloha Fujian, le thepa ea eona ea 'mele le ea lik'hemik'hale, motsoako oa amino acid le tatellano ea masala a 22 amino acid ho N. -terminal li ile tsa khethoa.Li Yuesheng et al.(1985) a arola le ho hloekisa PLA2 e 'ngoe ho tloha mahloko a Viper rotundus Fujian.Subunit ea PLA2 * ke 13 800, ntlha ea isoelectric ke 10.4, 'me mosebetsi o khethehileng ke 35/xnioI/miri mg LD5 e kenngoa ka methapong ea litoeba.Ke 0.5 ± 0.12mg/kg.Enzyme ena e na le litlamorao tse hlakileng tsa anticoagulant le hemolytic.Molek'hule e chefo ea PLA2 e na le mesaletsa e 123 ea mefuta e 18 ea li-amino acid.Molek'hule e ruile ka cysteine (14), aspartic acid (14) le glycine (12), empa e na le methionine e le 'ngoe feela,' me N-terminal ea eona ke masala a serine.Ha ho bapisoa le PLA2 e arohaneng le Tuguang, boima ba molek'hule le palo ea masala a amino acid ea li-isoenzyme tse peli li tšoana haholo, 'me motsoako oa amino acid le oona o tšoana haholo, empa palo ea aspartic acid le masala a proline e batla e fapane.Chefo ea noha ea Guangxi king cobra e na le PLA2 e ruileng.Shu Yuyan et al.(1989) e arolelitse PLA2 ho tsoa ho chefo, e nang le ts'ebetso e khethehileng ka makhetlo a 3.6 ho feta chefo ea pele, boima ba molek'hule ea 13000, motsoako oa masala a 122 a amino acid, ntlha ea isoelectric ea 8.9, le botsitso bo botle ba mocheso.Ho latela maekerosekoupo ya elektronike ya phello ya PLA2 ya motheo diseleng tse kgubedu tsa madi, ho ka bonwa hore e na le phello e totobetseng lerang la disele tse kgubedu tsa madi a motho, empa ha e na phello e totobetseng diseleng tse kgubedu tsa madi.PLA2 ena e na le phello e hlakileng ea ho lieha ho lebelo la electrophoretic ea lisele tse khubelu tsa mali ho batho, lipōli, mebutlanyana le likolobe.Chen le ba bang.Enzyme ena e ka thibela ho bokellana ha platelet ho bakoang ke ADP, collagen le sodium arachidonic acid.Ha khatello ea PLA2 e le 10/xg/ml~lOOjug/ml, ho kopana ha platelet ho thibetsoe ka botlalo.Haeba liplatelete tse hlatsoitsoeng li ne li sebelisoa e le lisebelisoa, PLA2 e ne e sitoa ho thibela ho bokellana ha 20Mg/ml.Aspirin ke inhibitor ea cyclooxygenase, e ka thibelang phello ea PLA2 ho liplatelete.PLA2 e ka thibela ho kopana ha platelet ka hydrolyzing arachidonic acid ho kopanya thromboxane A2.Motsoako oa tharollo ea PLA2 o hlahisoang ke chefo ea Agkistrodon halys Pallas Profinseng ea Zhejiang e ile ea ithutoa ka ho sebelisa selikalikoe sa dichroism, fluorescence le ho monya UV.Liphetho tsa liteko li bonts'itse hore ketane e kholo ea enzyme ena e tšoana le ea mofuta o tšoanang oa enzyme e tsoang mefuteng e meng le genera, sebopeho sa skeleton se ne se e-na le ho hanyetsa mocheso hantle, 'me phetoho ea sebopeho tikolohong ea asiti e ne e ka khutlisoa.Motsoako oa activator Ca2 + le enzyme ha e ame tikoloho ea masala a tryptophan, ha inhibitor Zn2 + e etsa se fapaneng.Tsela eo pH ea tharollo e amang tšebetso ea enzyme e fapane le li-reagents tse kaholimo.
Ts'ebetsong ea ho hloekisa PLA2 ea chefo ea noha, ntho e totobetseng ke hore chefo ea noha e na le litlhōrō tse peli kapa ho feta tsa PLA2.Ketsahalo ena e ka hlalosoa ka tsela e latelang: ① ka lebaka la boteng ba isozymes;② Mofuta o mong oa PLA2 o entsoe ka polymerized ka mefuta e fapaneng ea metsoako ea PLA2 e nang le litekanyo tse fapaneng tsa limolek'hule, tseo boholo ba tsona li leng ka har'a 9 000 ~ 40 000;③ Motsoako oa PLA2 le likarolo tse ling tsa mahloko a noha li thatafatsa PLA2;④ Hobane bond ea amide ho PLA2 e entsoe ka hydrolyzed, tefiso ea fetoha.① Mme ② e atile, ntle le mekhelo e fokolang feela, joalo ka PLA2 ho CrWa/w chefo ea noha
Ho na le maemo a mabeli: ① le ②.Boemo ba boraro bo fumanoe ho PLA2 mahlokong a linoha tse latelang: Oxyranus scutellatus, Parademansia microlepidota, Bothrops a ^>er, noha ea Palestina, noha ea lehlabathe, le rattlesnake e tšabehang km.
Sephetho sa nyeoe ④ se etsa hore lebelo la ho falla ha PLA2 le fetohe nakong ea electrophoresis, empa sebopeho sa amino acid ha se fetohe.Li-peptide li ka rojoa ke hydrolysis, empa ka kakaretso li ntse li tlanngoe hammoho ke li-bond tsa disulfide.Bohloko ba noha ea bochabela ea pit rattlesnake e na le mefuta e 'meli ea PLA2, e bitsoang mofuta oa a le mofuta oa p PLA2 ka ho latellana.Phapang pakeng tsa mefuta ena e 'meli ea PLA2 ke amino acid e le' ngoe feela, ke hore, glutamine ka molek'hule e le 'ngoe ea PLA2 e nkeloa sebaka ke glutamic acid ho molek'hule e' ngoe ea PLA2.Le hoja lebaka le tobileng la phapang ena le sa hlaka, ka kakaretso ho lumeloa hore le amana le ho felisoa ha PLA2.Haeba PLA2 e chefo ea noha ea Palestina e lula e futhumetse ka chefo e tala, lihlopha tsa ho qetela limolek'huleng tsa eona tsa enzyme li tla ba ngata ho feta pele.Ho tloha ho C PLA2 e arohaneng le mahloko a noha e na le N-terminal e 'meli e fapaneng,' me boima ba molek'hule ke 30000. Ketsahalo ena e ka 'na ea bakoa ke asymmetric dimer ea PLA2, e tšoanang le symmetric dimer e entsoeng ke PLA2 ka chefo ea eastern diamondback rattlesnake. le western diamondback rattlesnake.Cobra ea Asia e entsoe ka mefuta e mengata ea mefuta-futa, e meng ea eona e sa tsejoe hantle ka lihlopha.Ka mohlala, se neng se bitsoa li-subspecies tsa Cobra Outer Caspian se se se tsejoa
E lokela ho amahanngoa le Outer Caspian Sea Cobra.Kaha ho na le li-subspecies tse ngata 'me li kopantsoe hammoho, motsoako oa chefo ea noha o fapana haholo ka lebaka la mehloli e fapaneng,' me litaba tsa PLA2 isozymes le tsona li phahame.Ka mohlala, chefo ea cobra
Bonyane mefuta e 9 ea li-isozyme tsa PLA2 tsa r ^ll li ile tsa fumanoa ho tsona, 'me mefuta e 7 ea li-isozyme tsa PLA2 e ile ea fumanoa mahlokong a mofuta o monyenyane oa cobra Caspian.Durkin et al.(1981) o ithutile litaba tsa PLA2 le palo ea li-isozyme tse chefong tse fapaneng tsa linoha, ho kenyeletsoa chefo ea cobra e 18, chefo ea mamba e 3, chefo ea marabe e 5, chefo ea rattlesnake e 16 le chefo e 3 ea linoha tsa leoatle.Ka kakaretso, ts'ebetso ea PLA2 ea chefo ea cobra e phahame, ka li-isozyme tse ngata.Ts'ebetso ea PLA2 le li-isozyme tsa chefo ea marabe li mahareng.Ts'ebetso ea PLA2 ea chefo ea mamba le chefo ea rattlesnake e tlase haholo kapa ha e na ts'ebetso ea PLA2.Ts'ebetso ea PLA2 ea mahloko a noha ea leoatle le eona e tlase.
Lilemong tsa morao tjena, ha ho e-s'o tlalehoe hore PLA2 e chefo ea noha e teng ka sebōpeho sa dimer e sebetsang, joalo ka eastern rhombophora rattlesnake (C. snake venom e na le mofuta oa mofuta oa a le mofuta oa P PLA2, tseo ka bobeli li entsoeng ka lihlopha tse peli tse tšoanang. , mme ke dimerase feela e nang le eona
Ketsahalo.Shen et al.e boetse e etsa tlhahiso ea hore feela dimer ea PLA2 ea chefo ea noha ke mofuta o sebetsang oa enzyme.Boithuto ba sebopeho sa sebaka se boetse se paka hore PLA2 ea western diamondback rattlesnake e teng ka sebopeho sa dimer.Motsoako oa Piscivorous
Ho na le PLA tse peli tse fapaneng ^ Ei le E2 ea mahloko a noha, moo 仏 e leng teng ka sebopeho sa dimer, dimer e sebetsa, 'me monoma ea eona e arohaneng ha e sebetse.Lu Yinghua et al.(1980) o ile a tsoela pele ho ithuta ka thepa ea 'mele le ea lik'hemik'hale le kinetics ea karabelo ea E. Jayanthi et al.(1989) e ile ea arola PLA2 ea mantlha (VRVPL-V) ho tsoa ho chefo ea marabe.Boima ba molek'hule ea monomer PLA2 ke 10000, e nang le liphello tse bolaeang, anticoagulant le edema.Enzyme e ka polima li-polymer tse nang le litekanyo tse fapaneng tsa limolek'hule tlas'a boemo ba PH 4.8, 'me tekanyo ea polymerization le boima ba limolek'hule ea li-polymers e eketseha ka ho eketseha ha mocheso.Boima ba molek'hule ea polymer e hlahisitsoeng ka 96 ° C ke 53 100, 'me mosebetsi oa PLA2 oa polymer ena o eketseha ka tse peli.
Nako ea poso: Nov-18-2022