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LҰP C Hӌ MӨ&&Ѫ6Ӣ DӲ L IӊU CҨU TRÚ C PRO T E IN
Phan MҥQK7Kѭӡng1
, Lâm Thӏ Hoà Bình1ĈһQJ1Kѭ7RjQ1ĈRjQ7KLӋn Minh1
TrҫQ9ăQ/ăQJ2
1
Khoa Công ngh
WK{QJWLQ7U˱QJĈ
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10 HuǤQK9ăQ1JKӋ%LrQ+zDĈӗng Nai
{thuong,binh,dangnhutoan,dtminh}@lhu.edu.vn
29LQ.KRDKFYj&{QJQJK9LW1DP
0ҥFĈƭQK&KL4XұQ73+ӗ&Kt0LQK
tvlang@vast-hcm.ac.vn
7yP WҳW 7uP NLӃP Vӵ WѭѫQJ ÿӗQJ YӅ FҩX WU~F EұF ED FӫD FiF SURWHLQ
WURQJFѫVӣGӳOLӋXFҩXWU~FSURWHLQOӟQOjPӝWEjLWRiQSKӭFWҥSYjÿzL
KӓLQKLӅX WKӡLJLDQ[ӱOê6ӕOѭӧQJFiFFҩXWU~FSURWHLQÿѭӧFNKiPSKi
QJj\FjQJJLDQJQKDQKFKyQJYjWURQJFiFFѫVӣGӳOLӋXYӅXWU~F
SURWHLQ YLӋF OұS FKӍ PөF FKR FiF SURWHLQ VӁ JL~S WKDR WiF WuP NLӃP VR
ViQKXWU~FWKӵF KLӋQQKDQKKѫQYjKLӋXTXҧ KѫQ7Uong bài báo này
WUuQKEj\PӝWSKѭѫQJSKiSOұSFKӍPөFFKRFѫVӣGӳOLӋXFҩXWU~FSURWHLQ
WK{QJTXD YLӋFSKkQWtFK FҩX WU~FWӯ ÿyU~WUD YHFWRU ÿһFWUѭQJYj[k\
GӵQJ PӝWXWU~FFk\GӵD trên các YHFWRUÿһFWUѭQJÿӇSFKӍPөFFKR
FҩXWU~FSURWHLQ9ӟL VӣGӳOLӋXÿmÿѭӧFOұSFKӍPөFYLӋFWuPNLӃP
PӝWXWU~FSURWHLQKRһFPӝWFҩXWU~FFRQWURQJSURWHLQWUӣQrQQKDQK
FKyQJYjFKtQK[iFKѫQ
7ӯNKRi&ҩXWU~FSURWHLQEұFEDOұSFKӍPөFFѫVӣGӳOLӋXSURWHLQ.
1. Ĉһt n ÿӅ
Protein mӝt chuӛi polypeptLGHÿѭӧc tҥo thành tӯ các axít amin. Nghiên cӭu
SURWHLQÿyQJYDLWUzTXDQWUӑng, vì chúng hoҥWÿӝng trong tҩt cҧ các quá trình sinh hӑc,
bao gӗm cҧ xúc tác enzym (tҩt cҧc phҧn ӭng hóa hӑc trong tӃ bào sӕQJÿѭӧc xúc tác
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bӣi enzyme protein), vұn chuyӇn các chҩWNKiFQKDXQKѭGѭӥQJNKtFiFLRQ«, tín
hiӋu. ĈӇ hiӇXÿѭӧc mӕi quan hӋ giӳa cҩu trúc chӭFQăQJ cӫa protein, các nhà nghiên
cӭu cҫn phҧi lҩy tӯ Fѫ dӳ liӋu cҩu trúc protein phân loҥi chúng thành các hӑ
protein khác nhau.VҩQ ÿӅ quan trӑng trong viӋc gom nhóm các protein dӵa trên sӵ
WѭѫQJÿӗng cҩu trúc nhҵm mөc tiêu:
o Phát hiӋn các mӕi quan hӋ tiӃn hóa
o Xác ÿӏQKFiFPRWLIÿRҥn lһp), nhӳng cҩXWU~Fÿѭӧc hình thành bӣi sӵ
sҳp xӃp cӫa các axit amin trong không gian ba chiӅu
o Phát hiӋn mӕi quan hӋ giӳa cҩu trúc và chӭFQăQJFӫa protein
o Hӛ trӧ trong viӋc thiӃt kӃ thuӕc trӏ bӋnh
o Phát hiӋn các trình tӵ FyOLrQTXDQÿӃn bӋQKXQJWKѭYjFiFEӋnh khác.
9ӟLVӵÿәLPӟLF{QJQJKӋYjSKiWWULӇQQKDQKFKyQJFӫDcác SKѭѫQJSKiSxác
ÿӏQKFҩXWU~FSURWHLQQKѭSKѭѫQJSKiS;-quang WLQKWKӇ, NӻWKXұWSKkQWtFKTXDQJSKә
NMR«PӝWVӕOѭӧQJOӟQ FiFFҩXWU~F FKLӅX FӫD FiFSKkQWӱSURWHLQ PӟLÿm ÿѭӧF[iF
ÿӏQK&iFXWU~FQj\KLӋQÿDQJÿѭӧFOѭXWUӳWҥLQKLӅXVӣGӳOLӋXWUrQLQWHUQHWYj
FXQJFҩSPLӉQSKtFKRFiFQKjQJKLrQFӭXFyWKӇNӇÿӃQ
o Ngân hàng dӳ liӋu protein PDB [1] (Protein Data Bank) thuӝc phòng thí
nghiӋm RCSB (Research Collaboratory for Structural Bioinformatics): bao
gӗm 73153 cҩu trúc
o SCOP Structural Classification of Proteins [2]: bao gӗm 38221 cҩu trúc
o CATH Protein Structure Classification [3]: bao gӗm 104238 cҩu trúc
o ModBase Database of Comparative Protein Structure Models (Sali Lab,
UCSF): bao gӗm 41140 cҩu trúc
7uPNLӃPVӵWѭѫQJÿӗQJYӅFҩXWU~FEұFba FӫDPӝWSURWHLQKRһFPӝWFҩXWU~F
con cӫDprotein EҩWNǤtrong FѫVӣGӳOLӋXFҩXWU~FSURWHLQngày càng OӟQ OjPӝWQKLӋP
YөNKyNKăQYjWӕQWKӡLJLDQ9uYұ\ FiFQKjVLQKKӑFÿDQJFҫQPӝWSKѭѫQJWLӋQÿӇWuP
NLӃPFѫVӣGӳOLӋXFҩXWU~FSURWHLQQKDQKFKyQJ YjKLӋXTXҧWѭѫQJWӵQKѭFiFK%/$67
[5] WuPNLӃP trong FѫVӣGӳOLӋXWUuQKWӵ %jLWRiQWuPNLӃPYjSKkQORҥLSURWHLQWKѭӡQJ
WUҧLTXDKDLJLDLÿRҥQU~WWUtFKÿһFWUѭQJP{WҧFKRSURWHLQ YjÿRVӵJLӕQJQKDXYӅÿһF
WUѭQJFӫDFiFSURWHLQÿӇSKkQORҥLFK~QJ
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ĈӇ WKӵF KLӋQ U~W WUtFK ÿһF WUѭQJ FӫD u trúc protein Fy UҩW QKLӅX WKXұW WRiQ,
WKXұWWRiQ&766>6@[ҩS[ӍFҩXWU~FFiF&Į[ѭѫQJVӕQJFӫDSURWHLQ EҵQJ PӝWÿѭӡQJ
VSOLQHPӏQYӟLÿӝFRQJWӕLWKLӇXVDXÿyXWUӳÿѭӡQJFRQJJyF[RҳQYjFҩXWU~FEұF
KDLFӫDPӛLQJX\rQWӱ&ĮWURQJPӝWPөFFKӍVӕGӵD WUrQSKpSEăP
ProGreSS [5@OjPӝWSKѭѫQJSKiS PӟL, WKӵFKLӋQU~WWUtFKÿһFWUѭQJWӯFҩXWU~F
NӃWKӧSYӟLWUuQKWӵWK{QJTXDPӝWFӱDVәWUѭӧWWUrQFҩXWU~F[ѭѫQJVӕQJFӫDSURWHLQ
ĈһFWUѭQJYӅFҩXWU~FFӫDQyWѭѫQJWӵQKѭFiFÿһFWUѭQJU~WUDWӯ&766ÿӝcong, góc
[RҳQYjWK{QJWLQFҩXWU~FEұFKDLFiFFKXӛLÿһFWUѭQJÿѭӧFWtQKWRiQWӯYLӋFVӱGөQJ
PD WUұQ ÿLӇP QKѭ 3$0 KRһF %/2680 *LӕQJ QKѭ &766 FiF ÿһF WUѭQJ U~W UD
ProGreSS NK{QJSKҧLOjÿһFWUѭQJFөFEӝ
7KXұWtoán PSIST[7] OjPӝWWURQJVӕFiFWKXұWWRiQKLӋXTXҧYuFyÿӝFKtQK[iF
WѭѫQJÿӕLFDR, ciFKWLӃSFұQFӫD WKXұWWRiQ36,67 ELӃQÿәLFiFWK{QJWLQFҩXWU~FFөF
EӝFӫDPӝWSURWHLQWKjQKPӝWWUuQK" YjGӵDtrên WұSFiF³WUuQKWӵ´ÿy [k\GӵQJPӝW
cây X WӕSKөFYөFKRYLӋFWuPNLӃP6RYӟi cách rút trích FiFÿһFWUѭQJFөFEӝWӯPӝW
axit amin GX\QKҩWthì cách rút trích ÿһFWUѭQJWKHRFӱDVәWUѭӧWWURQJKѭӟQJWLӃSFұQ
FӫD WKXұWWRiQ36,67 OjWӕWQYuYHFWRUÿһFWUѭQJKjPFKӭD FҧKDLWK{QJWLQWӏQKWLӃQ
xoay ӣ ErQ WURQJ Sau khi các veFWѫ ÿһF WUѭQJ ÿѭӧF FKXҭQ KyD FҩX WU~F SURWHLQ
ÿѭӧFFKX\ӇQWKjQKPӝWFKXӛLJӑLOjWUuQKWӵÿһFWUѭQJ-XWU~FFӫDFiFNêKLӋXÿѭӧF
UӡLUҥFKRi.
Tuy nhiên viӋc tìm kiӃm trên cây hұu tӕ thӵc sӵ FKѭDÿҥt hiӋu quҧ cao vӅ tӕFÿӝ,
thuұt toán PSISA[8] sӱ dөng hѭӟng tiӃp cұQWUtFKYHFWRUÿһFWUѭQJJLӕQJ36,67QKѭQJ
thay dùng y hұu tӕ thì thuұt toán y sӱ dөng mҧng hұu tӕ WURQJSKѭѫQJ SKiS
ÿiQKFKӍ mөc nhҵPQJFÿӝ tìm kiӃm. KӃt quҧ thӵc nghiӋm trong PSISA chӍ ra
rҵQJÿiQKFKӍ mөc bҵng mҧng hұu tӕ giúp WăQJtӕFÿӝ tìm kiӃPQKѭQJÿӗng thӡLFNJQJ
OjPJLDWăQJkhҧ QăQJVӱ dөng bӝ nhӟ vӟi hӋ sӕ OrQÿӃQKѫQVRi cây hұu tӕ QKѭ
trong PSIST.
7URQJEjLEiRQj\WUuQKEj\PӝWSKѭѫQJSKiSOұSFKӍPөFFKRFѫVӣGӳOLӋX
FҩXWU~FSURWHLQWK{QJTXDYLӋFNӃWKӯD WKXұWWRiQ36,67 ÿӇ U~WUDYHFWRUÿһFWUѭQJYj
WӯWұSFiFYHFWRUÿһFWUѭQJEjLEiRÿӅ[XҩW[k\GӵQJPӝWFҩXWU~FFk\FKӍPөF GӵDWUrQ
YLӋFJKpSQKiQKFiFFKXӛLYHFWRUÿһFWUѭQJFҩXWU~FFk\Qj\YӯDJL~SKҥQFKӃYLӋFVӱ
GөQJEӝQKӟYjYӯDFKRSKpSWuPNLӃPWUrQNK{QJJLDQFӫDWRjQEӝFiFFҩXWU~FWKXӝF
4"
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FiFKӑSURWHLQNKiFQKDX, ÿLӅXQj\JL~SFKRYLӋFWuPNLӃPPӝWXWU~FSURWHLQKRһF
PӝWWLӇXFҩXWU~FWURQJSURWHLQWUӣQrQQKDQKFKyQJYjFKtQK[iFKѫQ
&iFQӝLGXQJ FzQOҥLFӫDEjLEiRÿѭӧF WUuQKEj\QKѭVau: SKҫQWKӭKDLWUuQKEj\
SKѭѫQJSKiSOұSFKӍPөFGӳOLӋXXWU~FSURWHLQFiFKWKӭFU~WWUtFKYHFWRUÿһFWUѭQJ
FKXҭQKyDYeFWRUÿһFWUѭQJFNJQJQKѭYLӋF[k\GӵQJFk\FKӍPөFSKҫQWKӭEDQrXOrQ
PӝWVӕWKӱQJKLӋPWӯQJXӗQGӳOLӋXFҩXWU~FSURWHLQ YLӋF WUX\YҩQWUrQQJXӗQGӳOLӋX
Qj\SKҫQFXӕLFQJWUuQKEj\PӝWVӕÿiQKJLiYjNӃWOXұQ
2. /ұSFKӍPөFGӳOLӋXXWU~FSURWHLQ
a) 5~WWUtFKYHFWRUÿһFWUѭQJ
0ӛLSURWHLQOjPӝWKӧSFӫDPӝWFKXӛLFyWKӭWӵFiFD[LWDPLQUHVLGXHÿѭӧF
OLrQNӃWYӟLQKDXLFiFOLrQNӃWSHSWLGH0ӛLUHVLGXHJӗPPӝW&D , các N C khác.
&KLӅXGjLFӫDOLrQNӃWJyFOLrQNӃWYjFiFJyF[RҳQKRjQWRjQ[iFÿӏQKFҩXWҥRYjKuQK
KӑFFӫDSURWHLQ
ĈӝGjLOLrQNӃWOjNKRҧQJFiFKJLӳDFiFQJX\rQWӱÿѭӧFLNӃW ÿѭӧFWtQKEҵQJ
ÿѫQ Amstrong (
o
A
)YjJyFOLrQNӃWOjJyFJLӳDKDLOLrQNӃWQJKRiWUӏFӫDFQJPӝW
QJX\rQWӱ9tGөÿӝGjLOLrQWJLӳDSQJX\rQWӱ1-C là 1.33
o
A
JyFOLrQNӃWJLӳD
CD-N và N-C là 1220.
Hình 1
ĈӝGjLOLrQNӃWYjFiFJyFOLrQNӃWJLӳDFiFQJX\rQWӱ
*yF[RҳQGQJÿӇP{WҧFiFFҩXWU~FFyWKӇ[RD\TXDQKFiFOLrQNӃW*LҧVӱWDFy
EӕQ ngX\rQWӱÿѭӧFNӃWQӕLWK{QJTXDED OLrQNӃW%i-1, Bi Bi+1WKuJyF[RҳQFӫDPӕL
OLrQW%i ÿѭӧFÿӏQKQJKƭDEҵQJJyFQKӓQKҩWFӫDFiFKuQKFKLӃX%i-1 Bi+1 OrQPһW
SKҷQJYX{QJJyFYӟL%i
5"
"
Hình 2
&iFJyF[RҳQI, MZ JLӳDFiFQJX\rQWӱ
ĈӇFKөSÿѭӧFFiFÿһFWUѭQJFөFEӝWFiFKFKtQK[iFKѫQ FҫQSKҧLWUtFK[XҩW
FiFÿһFWUѭQJWӯPӝWWұSFiFUHVLGXHFөFEӝĈӇWҥRUDYHFWRUÿһFWUѭQJFөFEӝÿҫXWLrQ
P{WҧWӯQJUHVLGXHULrQJELӋWYj[iFÿӏQKVӵOLrQKӋJLӳDPӝWFһSUHVLGXHYjJLӳDPӝW
WұSFiFUHVLGXHYӟLQKDX9ӟLPӛLUHVLGXHÿӝGjLOLrQNӃWCD-N1.46
o
A
OLrQNӃW&D-C
1.51
o
A
YjJyFJLӳD&D-N CD-C là 11601KѭYұ\WҩWFҧFiFWDPJLiFWҥRQrQWӯFiF
QJX\rQWӱ1-CD-&FӫDPӛLUHVLGXHOjWѭѫQJÿѭѫQJQKѭQKDXYjPӛLUHVLGXHFyWKӇÿҥL
GLӋQEӣLPӝWWDPJLiF
.KRҧQJ FiFK G JLӳD PӝW S UHVLGXH ÿѭӧF [iF ÿӏQK GӵD WUrQ NKRҧQJ FiFK
EXFOLGH JLӳD KDL QJX\rQ Wӱ &D FӫD FK~QJ &{QJ WKӭF ÿѭӧFVӱ GөQJ ÿӇWtQK WRiQ
NKRҧQJFiFKJLӳDhai residue
(1)
Góc T JLӳDPӝWSUHVLGXHÿѭӧF[iFÿӏQKEҵQJJyFJLӳDKDLPһWSKҷQJWҥRQrQ
Wӯba QJX\rQWӱ1-CD-&FӫDPӛLUHVLGXH
Hình 3
. .KRҧQJFiFKYjJyFJLӳDKDLUHVLGXH