A model has been proposed (Lahev and Chans, 1982) in which solid surfaces can act as a site for catalytic activity of condensation reactions for certain biomolecules. From this model, the adsorption characteristics of 5'ATP and 5'AMP onto the surface of CaSO4 2H2O was chosen for study. It has been proven that 5'ATP and 5'AMP do adsorb onto the surface of CaSO4. Studies were then made to determine the dependence of adsorption versus time, concentration, ionic strength and pH. It was found that the adsorption of the nucleotides is highly pH dependent, primarily determined by the phosphate acid groups of the nucleic acid molecule. From this investigation, the data obtained are discussed in relation to the model for the prebiotic earth

Calderon, J.

Sweeney, M. A.

English

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t 
l 	 4	 ^	
_ ,._. 
	
^	
*'.yam...	 Je 
	
''
- '	 FINAL TECHNICAL REPORT	 ._
111	
^i
SF
'y	 flf
i
An Investigation of the Adsorption Characteristics.,
of 5'ATP and 5 1 AMP onto the Surface of CaSO^•2H2O
r
John Calderon and M. A. Sweeney
(NASA-CE-177'101) AN INVESTIGAIION OF THE
	 N86-29005
a	 ADSORPTION CHAR AC7ER-1SZICS CF 5 PRIME ATP
AND 5 PRIME AMP CNTO THE SURFACE. OF CaSO SUB
4 X 2H SUB 2 0 Final Technical Report
	 Unclash -
(Santa Clara Univ.) 13 p
	 CSCL 07D G3/25 43234
..
NCC 2-170 UNIVERSITY OF SANTA CLARA
c/oSponsored Projects Office`
Dr. James Lawless ISanta Clara, CA 950.53
,u
y
a
r=es.
ORIGIN-AL Me ,
 Is
OF POOR 'QUAUTX
SUMMARY
A model has been Pro p osed LLahay and ch an 5 v 198 2) in
which solid surfaces can act as a site for catal y tic activity
of condensation reactions for certain biomolecules. From
this modelr the _dscr• p tion characteristics of VATF' and 5'AMF
onto the s+!r•fece of CsSO4 • 2H-.Q was chosen for study. It has
been Proven that VATr and VAMP do adsorb onto the surface
of 0_<50+. Studies were then made to determine the de"ren-
danTe	 of	 adsorption versus time, concentr•ation y ionic
stren g th and PH. It was found that the adsor p tion of the
nucleotides is hi gh!? PH dependents Primaril y determined by
the Phos p hate acid arour= o+ the nucleic acid molecule. From
this inve.,timationy the oa' ►_a obtained is discusser in
r•elatiur: to the the model for the Pr•ebiot.ic earth.
introduc tion
T he Po=ssible role of soluble :.alts in chemical evolution
Wes recentin di _cu_set in relation to fluctuatin g Pr•ebiatic
envir onments Whe' y. and Chan5s 1';'82?. In this environments a 
modal was Pro posed in which a hydratiDn- dehydration system
	
•	 .r
could have been res ponsible for reactions of biomolecules.'
Lurin g the deh y dration stake of such a model, some bio-
molecules. tend to leave the solution and concentrate at
certain mi.croonvironments, such as micelles and assr•esatest r
A
at the li:ct+_lid-has interface+	 and at the emer g in g solid
surface.. In addition to inor g anic cla y s ►- cr ystals of
soluble salts ma y have acted as sites for biomolecu_les to
leave the solution.
	
In a--fluct.uatin g envir6mmenty such as a tideeoolt lak.ey	 ^ s
or a3 ondr some of the dissolved salts basin to leave solution T
and form solid cr ystals u p on deh ydration.	 It is on these
7	 117
	
It	 '
	
f1 f	 !
1-
ORIGINAL. P C-Fl-
 IS	 e 2
OF POOR _QUAD'
solid	 cr vstals
	 that	 biomolecules	 can	 adsorb and .Pos-_iolu
a
roact	 with	 one	 another	 to
	 fGrrt,	 Grsiar(1C
	 cOn,'rle::es,
	 Ti,er,y	 upon
T2h-_ d restiCiris	 Liath	 th e 	 Ci omolecules	 and	 metal	 salts	 dissolve
N
into Solution to re p eat the process.
In	 one
	 investiaation
	 (Ri_.CIF•ony	 O'Harar
	 LahavY	 Lawless
S.^S2? y	 it	 was	 f o und
	 that•	 J ' f,T P 	 catales	 the ! formation
	 of
C7l'_0 11e	 C,1.i=:ortnGrs.	 It	 was	 also
	
found. that
	 a ddit ion of	 M!g CL.
Ctr`	 =,:tCl`:
	
lrtc	 v.reased	 th e 	leI d
	b y	 enhancin g 	 the	 thermal E'
f st-3bil .tv	 of	 5'ATP.	 It	 was thn it ht
	
th;A	 somehow	 the its{-t	 and *^
-1-1	 ions	 retarded	 the
	 r-- YroIYsi_•	 of	 the	 of	 the ATP:	 which :+
would	 flow a ­;i-eater concentration of ATP to
	 react with	 the
Rt ji., was
	 there	 a sub j ect•	 of
	
cur• _osit4	 as	 to	 the	 means	 by
^rti;_•h	 thF
	
G1
	
1F	 =alt:ct^^d
	 ir,
	
r•i •y t	 dins	 this	 brGak.rGwn.
F-om	 t•ire	 ofor• en.ent: onE•c	 nfc, g el r	 ones	 0a?n	 conceive
	 of	 a	 Primor- 
_ ­P,1	 1ak.e	 or	 P ondi	 ccint_ifin:E:	 soluble	 sait>>
	 nucleic	 acid=.,,
>rsd	 aiiiino	 acids.	 Darin-	 rehL.-dr•ation,
	 the	 concentration	 of
-	 the, soluble salt	 soon	 reaches a Point at which the salt is at:
.its saturation	 level,	 An	 further-deh y dration will cause the
salt,	 tct	 form	 its	 hv(Jrated ersst-als:
	 on which the adsor p tion r
of	 biomoleclules	 carp taE:,e-Placer
	 5'ATP
	 hein5
	
one	 of
	
them,
0nc•F, 	E:dsortwed	 onto	 the	 surface	 of	 the
	 salty
	 condensation
rr_-actions cars bec • onte more frD orable	 due to the	 lower	 entropy i
of	 the	 o!-stem	 •_red	 enhanced	 thermal
	 st:;bi1 it y	 of	 the
:1^.Ji:1^:?Gelds
I t
	 is with	 this scenario	 in at i nd 	 that Ex p eriments	 ir,
	
a
l.at-lorator y 	were	 conceived.	 Since	 it	 was	 thought	 that r•,ucleic
-	 -	
-y cids .^rrd un^ina a c -As were adsorbed onto the surface
	 of	 the
i
v
IL
ORIOINA' ^. Pc=z b	 ! • S e 3
no 
POOR 'C UALITY
►aetaI
	 sal is	 e'.: =o rirrents
	
were	 devised	 to	 mea-sure	 the	 amount
sr	 characteri stics of	 suc h 	if	 -1,^..	 The	 tword	 ar^_GrFtlOfrf
r,rro3.E, c•r,les	 _ hosen	 fur• 	this	 invest i _aation	 were 5'ATP	 and
r 'AMP	 Ori5inal	 studie s_	 of adsor p tion usin g the sol,uh,le salt
?^ g Cl_	 -howtd	 no me:3sureble adsorption. 	 It was then decided4
1.o use the le=_. =_' soluble salt C c-Ov	 in	 ho p es	 that	 a	 less
soluble salt will	 F-r•ovi.r;e a more stable	 surface area.
f
i Ex-pe r• i mental
The	 nucleic	 acid	 5'AT='	 was	 obtained	 from	 F•. E: L.
<u
Biochemicals.	 The	 5 AMP	 w:^s	 obtained	 from	 Boehrl.nser
M,, nnhuim	 PViarmaceutic• als.	 All	 salts	 wer e 	 anal y tical	 ausliti., ?
rez,,! ents	 and	 obtained	 frori,	 either	 Fishery	 •J.	 T.	 hak.err	 or
?,^ Ili_ncP...rodt	 All	 other•	 chemicals	 were	 of	 the	 Purest	 commer•-
ciel	 rivaiit y	available.	 - All	 solutions	 were	 Pre p ared	 with M
filtered y 	ion-e;:c•har, g er	 hi g h	 rurit^_­, 	 water.
M c ..q
Saturated solutions of CaSC i	 wove Pre p ared at	 22	 C	
cis
o sdirr g 	excess	 salt	 {.::>	 0.24	 g !100	 mL)	 to	 the volume of	 water
I -olutions	 of	 lictuid wer e 	allowed to eQudesired.	 The	 ^	 liorate
R c,ver•rnirsht	 to	 ensure	 saturation.	 All	 solutions- of	 5'ATf• 	and •
5'AMP were Pr• ep ared'vol,ume.trical1v usirt5 the saturated 	 Ca80,
as dilutent.
i
in	 all	 i x p eriments^	 0.500	 +	 .001	 3	 of	 solid	 CaCO,-	 2H. ;O
was	 wFiShcd	 into	 13x100mn,	 screw-toe	 test tu b es.	 To this:
rive	 millilitter• s	 of	 saturated	 Ca'O^	 solution	 with	 the
desired concentration of they dissolvers hiomolecule
	 (	 0.05 mM)
was z dried.	 If PH ad ustrrent were necessary then 	 were	 made
at	 this	 time -usin g 	1.0M	 (or	 less	 when necessar y )	 HCJ	 or NaOH`
. -
	
".	 . 	 L.	 um.	 ,.. i
 r. 'a='}nrr`
	
•f... '1'^:.t'F'
	
^S.'^
•' 3
	_ 	
.y'A	 mayy:: 
	 ..	 '- zm)
f
_
Pate 4
OF POOR QUA
solutions The test tubes were users sealer with a teflon C
coated screw-ca p and allowed to eQuilibr•ate. The PH was
measured usin g a Beckman PH meter with comb ination elec-
trode.
All	 experimental	 solutions	 were	 shaken	 for;	 at	 least
_I
three!	 i-our%	 at	 22,C	 (room tem p erature)	 on a standard hori-
shaker. 	 30,4 0 -	 s^ont.al	 _ l.. 	 Ever y	rs;inutes	 (exce p t	 for 	 that j
were 
	
allowed to eeuil bbate ov rniaht) r	 each sam p le was vor-
texed to ensure efficient mixin g of	 solute	 hiomolecule	 and
solid	 salt:	 and	 to minimize occlusion of	 the t_iiomolecule as
an im p uritw	 in the salt c-rwstal	 lattice.	 After	 the	 appro-
. , late	 eCtUlltbrati •a s-s	 t.	 we-	 each	 sam p le	 was	 centrifu g ed	 for H4^
five minutes	 on	 -	 Ct ndard de k-a..c.t-• _anal y tical	 centrifu g e	 to
se p arate	 the	 su p	rnetant	 liouid	 from	 the solid salt.	 Low
,_.eac h were used as this affected the adsor p tion of the	 trio
-y
moi.eC• u l e	 and	 the	 PH	 of	 the	 solution.
An Mieuot was withdrawn and filtered 	 throug h	 0.45	 um
filters	 (Milli p ore	 Car p .4 to	 remove	 aria	 sus p ended	 salt
Par•ti.s_le = .	 The	 concentration of	 the	 lsupernatant
-	
c?uid	 and
^."
the	 ori g inal	 -stock	 solution	 was	 measured. b y ultraviolet
bsor p tion t4mix = 259 -nm for 5'	 ATF @ PH '7M- usins a Car y 14
douf1e--beam"	 recordin g _. s'p ectroPhotomet.er.	 The	 amount	 of
biomalecule adsorbed onto the solid- salt	 was	 determined	 as
the	 difference	 in	 UV	 absor p tion -between t he	 initial	 stock.
solutions and the measured sam p le solution after shak.ins.
Ionic	 strength	 mo ;surements..w:ere ma4	 ,using NaCl	 to vary
the concentration of ions over the solid salt. 	 The salt NaCl ­
wasas ad' ed to the oritinal saturated MO.	 solutions before thet
s^	
_ _
	 fir:--..	
w..
^ INA.
1	
I
Fuse
overni ght eauilibiation to ensure that the solution was
	
saturated. PH measurements were made of all sam p les after	 i
	the su1=•ernat:ant liQuis was filtered and measured for absorb-	 k
ance. In deter• minins the surface area of the salt y a 0.242
mM _solution o"i meth y lene blue indicator in saturated Ca8'04
was used. The absorbance of the meth y lene blue solution
TI
	662 acid) that was treated bw the some Procedure as in 	 ;1
r G ,^ ^, . _
	 ^r.,Gh w
	 rt ^^r d to 44= stocE	 M.+ NW1  -ere.	 +^e	 cE_e^in^ _Tar a -	 ^,,	 a_:	 ^o	 W	  ;
` blue	 solution	 at	 tide-	 save	 PH value an d the difference in
g
concentra tion determined.
.,	 f
0 Data and Discussion
In the	 first set of experiments+	 10.00 • ml	 of a	 45.8	 mM
. ., r•TF	 sa,.ur2,	 d Ca., ,	 solution was added to 2.000 9 of MO O '
ii
jj 2 r	 0.	 The final	 YATP concentration was measured to be	 10*5
a
nM.	 which	 indicatod	 an	 adsorp tion 	 of	 175	 nmoles	 WATP
adsorbed	 Per	 team	 of	 solid	 CaSO ' • 2H_ 0.	 It	 was	 this
experiment,	 that	 first
	
showed	 that the, Msor p tion of VATP
` could be measured.	 It was th en d eci ded to do sev e ral	 series
of exneiriments to characterize this adsorption.
The next set of ex p eriments were tp det`ermine wether	 or
not	 thi s_._ measured	 adsor p tion followe d 	a tansiu irian carve.
Exp erimy is were done to determine the adsor p tion of W ATP as
a	 function of final	 concentration.	 The	 results are_shown	 in
fin 1.	 As the g ra p h =indicetes, 	 the, adsor p tion is	 linear at
low	 concentrations,	 and	 be g ins to level off as the concen-
tration over	 the solid salt	 increases.	 In fit.	 21	 a p lot of
Lanjmuir	 adsor p tion isotherm shows that the adsor p tion fol-
r
OF POOR QUALITY
lows a '_c^rr^nojirian	 adsorrtiorlr	 "xcep t	 at	 very low concentra-
-t.i6n•_.' The bindin g constant for the adsor p tion is Kb = 1.30
I•
1'
104f tlfllr it	 in d icates	 a	 very	 weak,	 interaction I
;r
AL'SrR?rION w FINAL CONCENTRATION a
5'ATP m+r C.SQ4.2Ht0
300 ti
LAN'MUIRa ADSOnPTJCN ISOTHERM250
N	 •JCC3 	 ^^20
200
ADS
I
150 JSp3N
.ATP
ti
I' 100. .10 Kt 1.30.16
t
111 7.7440'
50
D,
T-22 C
0-
 0 - 10	 ZD	 3D	 4:0	 50	
OC O	
10	 7.J	 30	 40	 50
C^ (" $	 x,C, G...^.51P^
.L
v
- mt
Fi gure	 1.	 FiZur•e	 2.
The	 next	 inter^:c•tion thz:t	 was	 looKed	 at	 was the	 adsor p -
tion
	
_s a function of	 iortic	 stren g th	 (fi^.	 3). As expectii i
ADSORPTION vt. IONIC- STR :NGTH +
5 ATP .,i. C.S	 21j0
100
140 .r d ATP a.w ;4U-. _q'1
ADS.
120
1DO
6G
60 0	 OF	 I.0	 1.5	 2D	 25
M N.CI
Fi.'#ure	 3.
the	 edsorp tion	 goes down as the solubilit	 of 5'HTF' goes u
due to the increase of ionic activit y in the	 solution	 above
V.1,
7	 !1	 -
ORIG
the solid s al t.	 OF POOR JUALITY
The r,e::t >3 aranletEr• looked at was the adsorr-tiara versus,
tilde. Ph versus time was also messured from this e-Per•iment.
It. was at this Point in the investi gation that we decided to
also experiment with 5'H^MP• since this nucleotide was also
Present on the Primordial earth,
	 The results of the the	 j
stutiv are shown in fi g . 4 and Fi g . 5.	 I
1
i
ADSORPTION ,., TIME
	 pH vi TIMES'ITP .3 5 'AMPwt. C.S;--2HS0
	
90	 5'ATP..t SAM? ..^. Ca50 2i0250	 r,
5 ATP
.	 (	 ..	 5 AMP
.+ r ATP.., : 53 A(ue..)
200	 a0
k	 5 ATPr	 ADS
PH
150	 70 `^'rsa.••a^o
5 AMP
100	 60	
s'
rrdAMP...• 53.0(+t
-
)
50-5
	 10	 g	 PO	 SD	
ti:
TI11E(r.al 	 25 i	 0	 S	 10	 15	 20	 25t	
_. t
	
:.	 TIME(6.)
Fisljre . *	 Figure a.
Usin g _ eau imo1ar concentrations of 5'ATF' and 5'AMP IP the
dsor p tion p lot shows a g reater (almost twice as much)
adsor.-tion for ATP than AMP. This seems to -indicate that the
adsor p tion- is somehow lirak.ed to the extra two. Phosphate
rotj>3 s on the ATF' molecule. Further? the- , uilibration time
for VATP is "much faster than that of 5`A14P. This was imp or-	 k
t.snt onl y to st ive information about how lon g samp les should
WNo
OF POOR Qj ;A^,.I`ry	 F'	 e 8
v` e 	 eauilitrra.ted for on the shaker when doin g further ads orp-
ti orr	 st ud 	 e;.
I	
;_
Front Fi g S y	 one see =_	 that c:ctUili b`ration tim e for	 PH	 is
;. ' bout the s.:-me for ATP and AMP.
	 The sha pe of the curves how-
eve r- sf_-em to follow the sna<<e of the adsor ption curves.	 Uith -
Lhe ti ou-sht that the adsor--tion is der-end nt on the Phosphate'
`i
and the match of the sha pe of the`	 a='-sor p tion	 aria	 PH
=_ur B ess	 it	 was	 thou g ht	 that	 the	 adsor p tion	 is hi ghl y
 PH s
r_ ePendent {
This h-<>P =thesis was tested
	
in the	 ne; t
	 and
	 the	 most y,
diff i cult	 to control)	 sot of exp rimcnts.
	 the adsor p tion as
a. ' function
	 of	 PH.	 hue to the	 weeE:•	 buff er in g
	c apacit y ► 	 the
t	
"^
=J C.; t,:
	 Points	 between	 PH	 -E•	 were	 h ar d 	 to	 stabilizer	 and	 as
	
a-
I C"21Ulti
	
ortl^-• 	 `tarp	 two	 hours
	
of	 ee1jilihr•ation.
	
The	 result	 of
the
	
5"ATP	 :a{j sor• Ptior:	 vers us 	 r-H	 _:re	 shown	 in	 fis.
	 b.
ADSORPTION .. pH
ATP
.1tto^SD4 2610
f
150
125 t•:
ADS
100
l t
75
50
}.
25
0 ID 20!	 - 30	 40	 55	 6O	 7.0	 80	 90
r► 	 P H
{Fi g ure	 E.
py y
OF DOOR Q
As ut't e carp see? the arsor•I,tion curve follows that of a
weak:. sc•ir titration.
	 The curve has art end point of -5.2t
	 4
whict- is euite different front the 5'F+TP PK:!2 of 6.2.	 The
	 "I
dotted line show y
 wha t. wou1ej have been expected if the
	 >!
adsor p tion followed the de p r•otonation of the first Phosphate
p roton
	 Howevers this curve does lend cre redance to the
hvy--thesis thrst the _.ds^ar p tion is linked to the Phos phate
	 }	 ^
1	
^.
Tr: contrast. to 5'HTPY 5'AhP shows a curve that cleerl2
denionstr•ates an odsor^-tion that follows the dissociation of
the Phos phate F•rotorts. The curve shows endpoints at the e>:-
p ect: ed rsnle of the PK.-j's of 5'AI SF'.• which are PK,^l -
 2.3 and
x
r. l.^,	 E,^z (fis.
	 7).	 Front the p H o f	 1-27	 there
	 is no
t
ADSORPTION ., r1I	
Y: ;
--- -
-5 AMP e+m Ca50..2H40__
	
;^
1 100
	
» ..
ADS
75
la 
^ ^
50
25	 AMP,_: 53,1 (-.=M
011!0	 2D,	 3.0	 40	 SO	 60	 70	 60	 90	 IOLO
	 i
P H	 f
i
Fi !j re :4
r	 s..- ^-	 +•. - ^:^	 ranee,, the molecule is totall y Protonater y
	1
with a positi v e char-e on the basic nitrosen of the Puriroe
..^].^^!
' 	 F ase	 1^J
vase.	 Around	 PH 2.3s	 the first de p rotonetlon occurs y 	which
the formation	 ion.	 This	 allows	 theresults in	 of a Zwitter {
o; vIen	 of	 the	 to form a we k interaction with the, phos phate
s alt -crustal.
From PH 3-5r	 no further	 increase in adsor p tion is shown.
This	 is	 consistent	 with	 the	 fact	 that 	no	 further
e	 t	 G	 From	 PH	 6-8,	 a	 -	 lar ge^,C.-r•o,onatior^	 is	 takin g 	 P l a ce.
7
adsor p tion	 is found.	 This is Probabl y due to the extr•actioin
of the second p roton which chan g es the VAMP molecule from	 a t
Zwit.ter	 ion	 to	 an	 i on	 with	 a ne gative net char g e.	 This
formation of the ne gative char g e	 is	 im or•tanti	 for	 it	 not '•'
:_nla	 increases the adsor p tions	 but it leads one to Postulate
x
that the oxw ;ens on the	 Phos phat e 	 ar e 	 somehow	 interacting
y
Pith the Ca-	 ions in the	 salt	 lattice. ,r
In order to determine if the surface area did not change
over	 the PH	 r ang e studiedf	 Meth y lene Blue	 in d icator was used
to measure the surface area adsor p tion verses PH	 (Fie.	 8-). 4
ADSORPTION rr	 PH
USING WTHYLEN`^P.LUE_jNQ1CATQR
i
cc^^
W
a
Y
40
Q/
/n
,v
30 .:
20
a'
662 .. i
W1.1 CA:2.22'1O M j
0.0 0
2	 3	 4	 5	 6	 7	 9	 g
}
PH
Fi gure	 8.
tF'aE^e	 1
As	 shownr	 the surface area did not chan ge over the PH rense.
Ttii•s hel p s to	 insure that the adsor ption	 both `,'ATF'curves of
"i
i
` and 5 1 AMP are not in error due to chan g in:-^ surface area# m
Conclusion
As the data	 indicates+	 5'ATF' and `'AMP	 do	 arsorb	 onto
the	 surf ac*	 of	 CazO_ • 21 H,0.	 The adsor p tion	 is hif.ihls depen-
k' Bent on ionic strensth.	 This would account for the	 lack.	 of
mezGsur:3ble	 adsor p tion	 onto	 MZ-Cl. --the	 high	 _•oIub ilit`3 	 of
MILiC1.
	
would	 increase
	
the
	
ionic	 strerrf-th to a Point	 that	 the
nucleotide	 would	 ube	 z:lmost	 totall y	Soluble.	 This'	 is	 o
consideration that one prust, take	 into	 ace o unt	 When	 Postu- r
ii
a	 p o_,i:-:i.blu	 rrech art ism	 of	 adsor p t i on	 in	 a	 cwcling
j>e
	
c— ti on.
The
	
adsor p tion	 of	 the	 riucleotides	 is	 highly	 PH
de-r-endent.	 This	 is another p ar.saieter that must be taken	 into
account	 when	 coins	 cvc1in5	 reactions.	 The	 PH	 of	 the
h y dration	 waters	 the	 bufferi_rre ca p acit ,a of the metal salts t.;
used 	 dissolved COZ amount of water	 left	 in	 the	 dehL4dratiorr
test	 tubes	 and	 other	 factors	 car,	 chanae	 the	 eN of the
solution 'above `ithe metal	 salt and thus char:e-e-arsorptivit^.
The adsor p tion is Probabl y due- to the inter_ction of the
cJ;,vocn- p hos p hate moiet y interactin g with the Ca 	 ions in the
•
.rent¢crustal	 latti,--e.	 The	 ^	 r	 adsorr, tion of	 ATF'	 at•	 ectuirtrolar 1
f
concentrations	 and	 the	 PH	 de p e nde nce`	 of	 the	 adsorption
su pp 0rt,	 this.	 -While	 t h is	 interaction se-ems	 to be	 ionic!	 the
low	 bindin g 	constant	 (Kb =	 1.3.102)	 would	 indicate that the
bond	 formation	 is ver2 weal--,r	 and taus riot totall y	 ionic.
}	 '..
	
.; r..v.	
-' 	 ..,a^s	 u.sn.,,R,.-`#'t.••..','ki'ICRv:.'d:.
	 ^	 .. '^"M:..:: ^. ^	 ....	 'w5...A`k	 ..^ _4 	 F^+! .sc...
i
_ -
^
` ^,
,	 is	 •
f	 ., Pa5e 12 ,
t
Since it was the Pur pose of this investi gation to deter-
mine	 if FATE'	 and/or	 W AMP	 idsorb y 	if so yand under what is
r
conditions ►
'
this	 line of ex perimentin g is	 deemed concluded.
The	 direction that
	 the	 experiments	 will	 now take is to-
r,
i
continue where
	
evel ins	 ex periments	 were	 last examined I
i`
(Pi_.h por: et.	 al * )F	 and continue to exp lore the- conditions ^I
that live tho	 best	 wield	 of	 s-1 y c _ne	 oliMme rs. Further
t'
1
_directions also include usin g
 other nucleotides ► 	 metal saltsy
and amino acids to find out what combinations y i eld the	 best
results of com p lex biomolecules. .i
Of
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77
711Z j


An investigation of the adsorption characteristics of 5 prime ATP and 5 prime AMP onto the surface of CaSO sub 4 x 2H sub 2 O

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