scieee Science in your language
[en] (orig)

Importance of the polarity of the glycosaminoglycan chain on the interaction with FGF-1

Abstract

Heparin-like saccharides play an essential role in binding to the fibroblast growth factor (FGF)-1 and to their membrane receptors fibroblast growth factor receptor forming a ternary complex that is responsible of the internalization of the signal, via the dimerization of the intracellular regions of the receptor. In this study, we report the binding affinities between five synthetic hexasaccharides with human FGF-1 obtained by surface plasmon resonance experiments, and compare with the induced mitogenic activity previously obtained. These five oligosaccharides differ in sulfation pattern and in sequence. We have previously demonstrated that all the five hexasaccharides have similar 3D structure of the backbone. Consequently, the differences in binding affinity should have their origin in the substitution pattern. Subsequently, the different capacity for induction of mitogenic activity can be, at least partially, explained from these binding affinities. Interestingly, one of the oligosaccharides lacking axially symmetry (3) was biologically inactive, whereas the other (2) was the most active. The difference between both compounds is the order of the FGF-binding motifs along the chain relative to the carbohydrate polarity. We can conclude that the directionality of the GAG chain is essential for the binding and subsequent activation. The relative biological activity of the compounds with regular substitution pattern can be inferred from their values of IC50. Remarkably, the sulfate in position 6 of d-glucosamine was essential for the mitogenic activity but not for the interaction with FGF-1.

Read accessible full text

Importance of the polarity of the glycosaminoglycan chain on the interaction with FGF-1

Author: Muñoz García, Juan Carlos; García Jiménez, M. José; Carrero, Paula; Canales, Ángeles; Jiménez Barbero, Jesús; Martín Lomas, Manuel; Imberty, Anne; Paz, José L. de; Angulo Álvarez, Jesús; Lortat Jacob, Hughes; Nieto, Pedro M.
Publisher: Oxford University Press
Year: 2014
DOI: 10.1093/glycob/cwu071
Source: https://idus.us.es/bitstreams/09a56338-f62f-480a-b294-ded74519b31f/download
Fo Pee Re iew
Impo an
ce o he di ec ionali y o he glycosaminoglycan
chain on he in e ac ion wi h FGF-1
Jou nal:
Glycobiology
Manusc ip ID:
GLYCO-2014-00014.R1
Manusc ip Type:
Communica ions
Da e Submi ed by he Au ho :
n/a
Comple e Lis o Au ho s:
Nie o, Ped o; Ins i u o de In es igaciones Quimicas, Quimica Bio-o ganica
Muñoz-Ga cía, Juan Ca los; CSIC, Ins i u o de In es igaciones Quimicas,
Quimica Bioo gánica, Glycosys ems Lab.
Ca e o, Paula; CSIC, Ins i u o de In es igaciones Químicas, Quimica
Bioo gánica, Glycosys ems Lab.
Canales, Angeles; CSIC, CIB, Dep . o Chemical & Physical Biology
JIMENEZ-BARBERO, JESUS; CSIC, CIB, Dep . o Chemical & Physical
Biology
Ma in-Lomas, Manuel; cicBiomagune, Bio unc ional Nanoma e ials Uni
Imbe y, Anne; CERMAV-CNRS, Molecula Glycobiology
de Paz, Jose Luis; Ins i u o de In es igaciones Quimicas, Quimica Bio-
o ganica
Angulo, Jesus; Ins i u o de In es igaciones Quimicas, Quimica Bio-o ganica
Lo a -Jacob, Hugues; Ins i u de biologie s uc u ale, gagophile;
Ga cia-Jimenez, M. Jose; Ins i u o de In es igaciones Quimicas, Quimica
Bioo ganica, Glycosys ems Lab.
Key Wo ds:
Glycosaminoglican, Hepa in, FGF-1, SPR, p o ein-ca bohyd a e in e ac ion
Glycobiology
Fo Pee Re iew
Impo ance o he pola i y o he glycosaminoglycan chain on he
in e ac ion wi h FGF-1
Juan C. Muñoz-Ga cía,
[a]
M. José Ga cía-Jiménez,
[a]
Paula Ca e o,
[a]
Ángeles
Canales,
[b]
Jesús Jiménez-Ba be o,
[b]
Manuel Ma ín-Lomas,
[c]
Anne Imbe y,
[d]
José L.
de Paz,
[a]
Jesús Angulo,
[a]
Hugues Lo a –Jacob,
[e]
and Ped o M. Nie o*
[a]
a) Ins i u o de In es igaciones Químicas, CSIC, Amé ico Vespucio, 49, 41092 Se illa, Spain
b) Cen o de In es igaciones Biologicas, CSIC, Rami o de Maez u 9, Mad id 28040, Spain
c) CIC biomaGUNE, Bio unc ional Nanoma e ials Uni , San Sebas ian 20009, Spain
d) CERMAV-CNRS, BP 53, 38041 G enoble, cedex 9, F ance
e) Ins i u e de Biologie S uc u al Jean Pie e Ebel, CNRS 41 ue Jules Ho owi z, F-38027 G enoble Cedex 1,
F ance
Phone (+) 34 954 489568, Fax: (+)34 954 460565, e-mail: ped o.nie [email protected]
Keywo ds: Hepa in, Glycosaminoglycan, FGF-1, p o ein-ca bohyd a e in e ac ion, SPR
Wo d coun ing: 4173
Page 1 o 15 Glycobiology
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Fo Pee Re iew
Abs ac :
Hepa in-like saccha ides play an essen ial ole in binding o he FGF-1 and o hei memb ane ecep o s
FGFR o ming a e na y complex ha is esponsible o he in e naliza ion o he signal, ia he dime iza ion o
he in acellula egions o he ecep o . In his s udy we epo he binding a ini ies be ween i e syn he ic
hexasaccha ides wi h human FGF-1 ob ained by Su ace Resonance Plasmon (SPR) expe imen s, and compa e
wi h he induced mi ogenic ac i i y p e iously ob ained. These i e oligosaccha ides di e in he sulpha ion
pa e n and in he sequence. We ha e p e iously demons a ed ha all he i e hexasaccha ides ha e simila 3D
s uc u e o he backbone. Consequen ly, he di e ences in binding a ini y should ha e hei o igin in he
subs i u ion pa e n. Subsequen ly, he di e en capaci y o induc ion o mi ogenic ac i i y can be, a leas
pa ially, explained om hese binding a ini ies. In e es ingly, one o he oligosaccha ides lacking o axially
symme y (3) was biologically inac i e whe eas he o he (2) was he mos ac i e. The di e ence be ween bo h
compounds is he o de o he FGF binding mo i s along he chain ela i e o he ca bohyd a e pola i y. We can
conclude ha he di ec ionali y o he GAG chain is essen ial o he binding and subsequen ac i a ion. The
ela i e biological ac i i y o he compounds wi h egula subs i u ion pa e n can be in e ed om hei alues
o IC
50.
Rema kably, he sulpha e in posi ion 6 o D-Glucosamine was essen ial o he mi ogenic ac i i y bu no
o he in e ac ion wi h FGF-1.
Page 2 o 15Glycobiology
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Fo Pee Re iew
In oduc ion
FGF-1 is a membe o he Fib oblas G ow h Fac o amily ha in e ac s wi h hepa in/hepa an sulpha e
(Hep/HS) polysaccha ides and he memb ane ecep o s FGFRs. The o ma ion o a e na y complex be ween
FGF, FGFR and Hep/HS is he key s ep o he ac i a ion o he FGF signalling pa hway. This is a he o igin o
di e en cellula essen ial unc ions as egula ion o emb yonic de elopmen , homeos asis and egene a i e
p ocesses (Be n ield M e al. 1999, Eswa akuma VP e al. 2005, K euge J e al. 2006). Dime iza ion o he
ecep o s and subsequen in acellula au ophospho yla ion ac i a es a mi ogenic esponse h ough an enzyma ic
cascade (Mohammadi M e al. 2005, Pelleg ini L e al. 2000, Schlessinge J e al. 2000).
The helical s uc u e o hepa in, a highly sulpha ed o m o HS, di ec s he sulpha e g oups owa ds
opposi e sides o i s longi udinal molecula axis (Mulloy B e al. 1993). Acco ding o ha , he i s
c ys allog aphic s uc u es o he hepa in and human FGF-1 complexes (pdb code: 1amx and 2amx)
co esponded o dime ic s uc u es linked by a egula hepa in chain in i s na i e helical s uc u e (DiGab iele
AD e al. 1998). Howe e , NMR da a in solu ion co esponded o a 1:1 complex (pdb code: 2e m) (Canales A e
al. 2006). Rema kably, he dime s ha e wo al e na i e symme y ela ionships: while o 1amx he FGF-1
p o eins a e ela ed by a cen e o symme y, in he case o 2amx, he symme y elemen is a plane along he
binding si e (DiGab iele AD e al. 1998). In addi ion, he e na y complexes o hepa in and FGF wi h he
ex acellula domains o he memb ane ecep o FGFR a e assembled in o wo di e en o ms (pdb codes 1 q9
and 1e0o espec i ely) (Schlessinge J e al. 2000)
,
(Pelleg ini L 2001, Pelleg ini L e al. 2000)
The analysis o hese s uc u es indica es ha he Hep/HS binding si e co esponds o a swallow dep ession
on he su ace o he g ow h ac o ha could be conside ed di ided in o wo sub-binding si es (Digab iele AD e
al. 1998). Consequen ly, as hepa in does no much change i s helical 3D s uc u e upon binding, in he
monome ic case as is he NMR complex (pdb code: 2e m)(Canales A e al. 2006) some o i s sul ama e g oups
will be di ec ed owa ds he sol en and will no in e ac wi h he FGF-1, as he s uc u al s udies ha e shown.
In o de o analyse he hepa in-FGF-1 binding mode, 2, a hexasaccha ide wi h axially non-symme ic
sulpha e g oups dis ibu ion and unable o o m FGF dime s was p epa ed (Ojeda R e al. 2002). The FGF-1
induced mi ogenic ac i i y o hexasaccha ide 2 was highe han 1 (de Paz JL e al. 2001), which co esponds o
he egula sulpha ion pa e n o hepa in (Angulo J e al. 2004) simila o he ecen ly isola ed om na u al
Page 3 o 15 Glycobiology
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Fo Pee Re iew
sou ces as hexame (Smi s N e al. 2010). This esul pe mi ed o disca d he dime iza ion o FGF-1 h ough a
chain o bound hepa in as a equi emen o he FGF-1 media ed bioac i i y. In e es ingly, 3, which p esen s
simila symme y on he sulpha e g oups dis ibu ion han 2, wi h espec o he longi udinal axis, was inac i e
(de Paz JL e al. 2005). The subs i u ion pa e n o 3 was designed o i wi h he equisi es p oposed by
Pelleg ini o maximise he in e ac ions and symme y in he e na y complex as i was deduced om he analysis
o di e en c ys allog aphic s uc u es (Pelleg ini L 2001). O he syn he ic oligosaccha ides wi h di e se
sul a ion pa e ns p epa ed in ou g oup lacking o sulpha e g oups in all he posi ions 6-O o glucosamines (4)
o in all he 2-O o idu ona es (4) we e also inac i e (Lucas R e al. 2003). Du ing he e ision o his manusc ip
a pape desc ibing he syn hesis o h ee hexasaccha ides and examining hei bioa ini ies p o iles o was
published (Roy S e al. 2014).
Recen ly pe o med was an in dep h analysis o he h ee-dimensional s uc u e o 3 using NMR and MD in
o de o sea ch o any s uc u al di e ences ha migh jus i y he loss o ac i i y (Munoz-Ga cia JC e al. 2013).
F om his analysis i was concluded ha 3 exhibi s he same main s uc u al ea u es cha ac e is ics o hepa in
han he analogues 1 and 2, which a e known o p omo e he in e ac ion wi h FGF-1; a) a well-de ined igid
helical backbone wi h ou esidues pe u n, b) a cha ac e is ic chai
1
C
4
- skew boa
2
S
O
con o ma ional
equilib ium o he idu ona e esidues, and c) a igid beha iou o he glycosidic linkages. This s uc u al
analysis allows o disca d any po en ial di e ence in he h ee-dimensional s uc u e ha could jus i y he
di e ences in he obse ed biological ac i i y be ween 2 and 3 (e.g. modi ica ion o he glycosidic linkages
geome y owa ds an an i disposi ion) (Munoz-Ga cia JC e al. 2013). Consequen ly, he main di e ences in
a ini y o FGF-1 among he hexasaccha ides 1-5 would be due o he capaci y o each sul ona e pa e n o
in e ac wi h FGF-1 as a unc ion o i s spa ial dis ibu ion along he chain.
Resul s
To in es iga e he abili y o he i e syn he ic oligosaccha ides, 1 – 5, o in e ac wi h human FGF-1, an
inhibi ion assay was se up. The g ow h ac o , ei he alone o coincuba ed wi h each o he i e molecules o be
analysed, was injec ed o e bo h a hepa in- unc ionalized senso chip and a s ep a idin senso chip, he la e
being used as a con ol su ace, and he in e ac ion was ollowed by Su ace Plasmon Resonance (SPR)
spec oscopy (Figu e 2). Injec ion o 8.8 nM o FGF-1 o e he hepa in su ace p oduced a binding esponse o
350 esponse uni s (RU) a equilib ium whe eas a esponse o 5 RU was obse ed o e he s ep a idin su ace
(da a no shown). Analysis o he esul s showed ha hese oligosaccha ides s ongly di e in hei abili y o
Page 4 o 15Glycobiology
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60

Fo Pee Re iew
p e en FGF-1-Hep binding (Figu e 2). The inhibi o y ac i i y o 1 was cha ac e ized by an IC
50
o 8.3 10
-8
M
whe eas 5 did no display binding ac i i y in he ange o concen a ions es ed indica ing ha , 2-O sulpha e
g oups we e essen ial o he in e ac ion (Angulo J e al. 2004). In con as , 6-O sulpha e g oups, ha a e
in ol ed in he biological ac i i y (Angulo J e al. 2004), seem o be dispensable o he in e ac ion wi h FGF-1,
wi h an IC
50
= 4.7 10
-7
M o 4.
Nex , o in es iga e he impo ance o he p esen a ion o he sul ona e g oups along he chain, he same
assay was used wi h 2 and 3 since bo h ha e an asymme ic sulpha e dis ibu ion. In e es ingly, i was obse ed
ha , 2 ea u es an IC
50
= 4.6 10
-7
M, hus simila o 4, al hough 2 has i e sulpha e g oups compa ed o six o
he egula oligosaccha ide. Finally, 3, which also displays six sulpha e g oups wi h an axially asymme ic
dis ibu ion, has a much lowe binding ac i i y, wi h an IC
50
= 1.6 10
-6
M. Thus, while he mi ogenic ac i i y
p e iously ob ained was 2 > 1 >> 3, 4, 5 (Angulo J e al. 2004), in he case o he binding a ini y he o de was 1
> 2, 4 >> 3 >> 5.
Discussion
Assuming a undamen al ole o he elec os a ic in e ac ions, and conside ing he s uc u al di e ences
be ween he hexasaccha ides, he sulpha ion pa e n should be a he o igin o he di e ences in he s eng h o
he in e ac ion and he e o e in he ac i i y. Appa en inconsis encies be ween he la ge IC
50
alues o 1
compa ed wi h 2, measu ed by SPR expe imen s, and he induc ion o mi ogenic ac i i y, which is la ge o 2,
can be explained conside ing he assembly o he e na y complex. This is essen ial o he biological ac i i y,
and addi ional hidden equi emen s may play addi ional oles (Pelleg ini L e al. 2000, Schlessinge J e al. 2000).
Compounds 2 and 3 , as hey ha e hei sul ona e g oups di ec ed owa ds one side o he molecula axis,
only can in e ac wi h FGF using one o hei hal . On he con a y, as he 3D-s uc u es o 1, 4 and 5 ha e an
axially symme ic dis ibu ion o sul ona e g oups, hey ha e he possibili y o in e ac wi h wo molecules o
FGF using wo opposi e sides o he oligosaccha ide in a sandwich like ashion, wi h wo simul aneous binding
e en s (Angulo J e al. 2004, de Paz JL e al. 2001, Lucas R e al. 2003). This obse a ion migh also explain he
obse ed di e ences be ween he mi ogenic ac i i y measu ed by p oli e a ion s udies (Angulo J e al. 2004) and
he ela i e binding s eng h o FGF-1, epo ed in his s udy.
The hepa in binding si e o FGF-1 could be di ided in o wo spa ially con iguous sub-si es (DiGab iele AD
e al. 1998). The i s one binds a isaccha ide GlcNS – IdoA2S – GlcN6S, in e ac ing ia h ee nega i ely
Page 5 o 15 Glycobiology
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Fo Pee Re iew
cha ged sulpha e moie ies (Saxena K e al. 2010). Such a angemen o cha ged g oups displays he p ope
numbe and o ien a ion o sul ona e g oups o es ablish a igh in e ac ion wi h FGF-1. Recen s udies ha e
e ealed key di e ences be ween FGF-1 and FGF-2 binding o GAG in his subsi e. Fo he case o FGF-2 he
isaccha ide ha in e ac s in subsi e a is he complemen a y one, Ido2S – GlcNS – Ido2S (Saxena K e al. 2010).
The second sub-si e in e ac s wi h a disaccha ide, GlcN6S – IdoA2S. A cen al idu ona e esidue wi h a non-
pa icipa ing sul ona e g oup links bo h mo i s. Rema kably, hexasaccha ides 2 and 3, display simul aneously
hese wo deco a ions o he in e ac ion wi h FGF-1 bu , in e e se o de i he pola i y o he chain is
conside ed.
In an a emp o ind a sa is ac o y explana ion o he lack o ac i i y o 3 wi h espec o 2, a molecula
modelling docking p o ocol was employed o analyse he molecula in e ac ions om a s uc u al pe spec i e.
Thus, he backbone o he mos ep esen a i e con o ma ion o 3, aken om 500 ns o un es ained molecula
dynamics ajec o y (Munoz-Ga cia JC e al. 2013), was manually supe imposed o he mos ep esen a i e
s uc u e o he NMR complex be ween FGF-1 and 2 (pdb 2e m). As he dis ances be ween he h ee sulpha e
g oups di ec ed owa ds he same side o he molecule we e simila , wo pola i ies o supe imposi ion we e used,
om he educing o non- educing end and i s e e sed al e na i e. We ha e employed as i s c i e ia, he
alignmen o he longi udinal axis o bo h ca bohyd a es. Howe e , he posi ions o he sul ona e and sul ama e
g oups o 3 we e no adequa e o he comple e in e ac ion wi h he complemen a y esidues o he p o ein. A e
ha , he non- educing end isaccha ide o 3 was manually docked in o he main sub-si e in he “ e e se”
o ien a ion. In his case, he es o he oligosaccha ide did no i in he comple e binding pocke and poin ed
owa ds ou side he complex. In addi ion, a s e ic clash was obse ed be ween he p o ein side chains and he
GlcN – IdoA – GlcN isulpha ed isaccha ide o 3 (see Suppl. In o. o desc ip ion o addi ional modes). The
impossibili y o assemble a complex wi h he comple e se o cha ged in e ac ions be ween he FGF-1 and he
hexasaccha ide 3, lead us o conclude ha he co ec pola i y o he GAG chain is essen ial o he in e ac ion
wi h he g ow h ac o (FGF-1).
We decided o pe o m docking calcula ions in o de o ge a deepe insigh in o he possible binding o 3 and
FGF-1. We ha e used Glide, i s using he Induced Fi Docking p o ocol wi h he s anda d condi ions and hen,
he esul s we e subjec ed o a un o Single P ecision Docking. In his case, he ocus was pu in o he h ee
saccha ides o he iad, leading o a displaced sequence. A ema kable supe imposi ion o he poses o his
egion was ound in he solu ions (see supplemen a y ma e ial).
Page 6 o 15Glycobiology
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Fo Pee Re iew
In e es ingly, 2 (Figu e 3a) has bo h sulpha e clus e s in he igh disposi ion o in e ac simul aneously wi h
bo h binding sub-si es while 3 is only capable o in e ac ing wi h he sub-si e a (Figu e 3) (Canales A e al. 2006).
This can explain he alue o IC
50
o 3, 3.5 old la ge han 2. This di e ence can be explained conside ing ha
he pola i y o he glycosaminoglican chain is essen ial o he maximum numbe o in e ac ions ake place.
While he sub-si e a is in e ac ing wi h 2 h ough he isaccha ide GlcNS – IdoS – Glc6S s a ing a glucosamine
in posi ion i, he equi alen isaccha ide ha binds he main subsi e in he case o 3 is shi ed o he GlcN a
posi ion i+4. The seconda y binding sub-si e does no es ablish any in e ac ion wi h 3, hus explaining he lowe
a ini y measu ed by SPR and he absence o mi ogenic ac i i y due o he ailu e o assemble o highe o de
complexes needed. The e o e, he in e ac ion be ween FGF-1 and 3 should be weake han 2. This should be he
cause why 2 and 3 showed such d ama ic di e ences in hei binding a ini y and bioac i i y in spi e o bea ing
he same wo binding mo i s, bu in opposi e o de .
Addi ional in o ma ion can be ex ac ed om he compa ison be ween he a ini y expe imen s and biological
ac i i y ones. Fo ins ance, he sulpha ion in posi ion 6 o glucosamine ha , acco ding o ou p e ious biological
esul s, is essen ial o he FGF-1 mi ogenic ac i i y (Angulo J e al. 2004), i is no o he in e ac ion wi h FGF-
1. Tha obse a ion migh be exploi ed in he design o po en ial inhibi o s o he FGF-1 media ed mi ogenic
ac i i y ha being able o in e ac wi h he FGF-1, he absence o his key g oup p e en he assembly o he
e na y ac i e complex, and he subsequen biological ac i i y. Ano he impo an conclusion ha can be
ex ac ed om ou wo k is he e idence o he s ong in luence o he pola i y o he GAG chain on he binding.
This also can be exploi ed o he design o inhibi o s ha in e ac ing wi h he FGF-1 hey do wi h he opposi e
pola i y and hey will no be able o o m he ac i e e na y complex.
In summa y, we ha e demons a ed ha he pola i y o he oligosaccha ide chain ela i e o FGF–1 is a
c i ical ac o o he s eng h o he bina y in e ac ion and u he assembly o he e na y complex (B own A e
al. 2013).
Ma e ials and Me hods
Syn heses o compounds 1 - 5 ha e been p e iously desc ibed (de Paz JL e al. 2001, de Paz JL and Ma in-
Lomas M 2005, Lucas R e al. 2003, Ojeda R e al. 2002).
Size de ined hepa in (Hep; 6 kDa) was immobilized on a Biaco e senso chip. Fo ha pu pose, Hep was
bio inyla ed a i s educing end by coincuba ion wi h 10 mM bio in/LC-hyd azine o 24 h a oom empe a u e.
Page 7 o 15 Glycobiology
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Fo Pee Re iew
The mix u e was hen ex ensi ely dialyzed agains H
2
O o emo e un eac ed bio in and eeze-d ied. Two low
cell o a CM4 senso chip we e hen unc ionalized wi h app ox. 2500 esonance uni s (RU) o s ep a idin as
desc ibed (C uble E e al. 2008) and bio inyla ed HP (5 µg/ml), in HBS-EP (10 mM HEPES, 150 mM NaCl, 3
mM EDTA, 0.005% su ac an P20, pH 7.4) was injec ed ac oss one low cells o ob ain an immobiliza ion le el
o 50 RU. The o he low cell was le un ea ed and se ed as nega i e con ol. Fo binding assays, 150 µl o
FGF-1 (8.8 nM), co incuba ed wi h a ange o concen a ion o he di e en oligosaccha ides, we e
simul aneously injec ed, a a low a e o 50 µl/min, o e he con ol and he HP su aces. The o med complexes
we e washed wi h unning bu e o 3 min and he senso chip su aces we e egene a ed wi h a 3 minu e pulse
o 2 M NaCl. Con ol senso g ams we e sub ac ed on line om HP senso g ams.
The p o ein da a bank s uc u es 1amx, 2amx and 2e m we e used o he p elimina y s udies o docking
desc ibed in his pape , pe o med wi h GLIDE (F iesne RA e al. 2004). The monome C om he 1amx
complex was isola ed om he es o he agg ega es and used o p epa e he model o he hexasaccha ide 3 wi h
FGF-1 by supe imposi ion o he isaccha ide o i s educing end wi h he one a he non- educing end o he
1amx and/o 2e m complexes aligning he sul a e g oups. Hyd ogens a oms we e added o he c ys allog aphic
s uc u e when i was necessa y using he Maes o p o ein p epa a ion module. The co esponding hexa- and
pen asaccha ides we e p epa ed and named consis en ly and using pa ial cha ges om GLYCAM (Ki schne
KN e al. 2008), ligand p epa a ion module was un and he s uc u e was minimized. A g id (10 x 10 x 10 Å)
cen e ed in he glycosaminoglycan was cons uc ed. We i s un an Induced Fi Docking wi h he s anda d
condi ions keeping he GLYCAM cha ges. The esul ing s uc u es we e submi ed o a Single P ecision
Docking, wi h a 10 Å g id using GLYCAM pa ial cha ges wi h an elec os a ic cu o o 2.0. The minimiza ion
was pe o med using OPLS-2005 o ce ield wi h a dielec ic cons an o 4
Funding
This wo k was suppo ed by CSIC (JAEP e_09_01999 o J.C.M-G and 2004FR0025), Jun a de
Andalucía (P07-FQM-02969), Spanish Minis y o Science and Inno a ion (CTQ2009-07168,
CTQ2012-32025, and CTQ2012-32605; and RYC-2007-01791 o J.A.), and he Eu opean Union
(FEDER).
Abb e ia ions
Page 8 o 15Glycobiology
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Fo Pee Re iew
293x305mm (300 x 300 DPI)
Page 15 o 15 Glycobiology
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60