Un ensayo de interpretación El ciudadano y los servicios de salud

(1 ) P ao tln o lY tio engyaes

T his experim ent was oonduoted in an endeavour to

d isc o v e r w hether th e fungi were capable o f d ig e s tin g t h e i r way a c ro ss th e m iddle la m ellae o f c e l l s . M iddle lam ella i s known to co n tain a la rg e q u a n tity o f p e c tin c h ie fly in th e form o f calcium p e o ta te , A red u ctio n in th e v is c o s ity o f sodium p o ly p e c ta te (o b tain e d from

Sigma Chemical C o,) by a fungal e x tr a c t, would in d ic a te th a t th e fungus had produced a p e c tin o ly tic enzyme

ex t race l l u l a r l y . T his would sug g est th a t i t was capable o f b re a k in g down th e p e o ta te in th e m iddle la m e lla .

Method

The experim ent which i s d e sc rib e d below, is

s im ila r to th a t designed by W instead and McCombs (1961) in t h e i r stu d y o f p e c tin o l y t i c and c e llu lo ly tic

enzyme p ro d u ctio n by Pvthium aphanidenaatum . In o rd e r to o b ta in th e f U n ^ l e x tr a c ts , th e fhngi were grown on a b a s a l medium c o n s is tin g o f th e fo llo w in g c o n s titu e n ts s -

KHgPO^ 3*0 grams

KgHPO^ 2 .0 «

Mg SO^.THgO 0 .5 ”

A sparagine 2 .0 "

D is tille d w ater 1000 ml

T his medium was converted to pH6 b efo re a u to c la v in g . Glucose was added to h a lf o f t h i s medium and

sodium p o ly p e c ta te to th e o th e r h a l f , both a t th e r a te o f 10 grams p e r l i t r e . The media were s t e r i l i z e d in th e manner d escrib ed in S e c tio n 2 b (i)(b ) and dispensed

in 25ml q u a n titie s in p re v io u sly s t e r i l i z e d 25Gmi Brlenm eyer f la s k s . They were th en in o c u la te d from

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âB BO à llâ i amnumhlla. ^ and E_1 Nbloh were

a c tiv e ly growing on m alt e x tra c t a ^ r f o r th re e weeks. The experim ent was s e t up in d u p lic a te and th e fla s k s in cu b ated a t 23*C. A fte r fo u r weeks, th e co n ten ts o f th e d u p lic a te d fla s k s were mixed and f i l t e r e d th r o u ^ g la ss wool and ^ u s e . The f i l t r a t e was regarded a s an ** enzyme extract** and was used to determ ine th e lo ss o f v is c o s ity o f sodium p o ly p e c ta te .

The "enzyme extracts** were b u ffe re d a t pH 5*3 and pH 7*0 w ith sodium a c e ta te /a c e tic a c id b u ffe r and when th ey were not used w ith in one hour o f f i l t r a t i o n , th ey were s to re d in a deep fre e z e , A co n stan t tm aperature Warburg w ater b ath was s e t up a t a tem perature o f

29,4^C ( j 0 ,0 5 ), A Cannonr-Penske v isco m eter B s/lp /C P

s iz e 300 was u sed .

There were two enzyme e x tr a c ts p e r fungus, ( i ) a ** glucose enzyme extract** where th e fungus v;as grown on th e b a sa l medium + glucose and ( i i ) a " p e o ta te eniqnae e x tra c t" where sodium p o ly p e c ta te had been added to th e b a s a l medium,

P or each ftmgus 6 x 100ml Erlenm eyer fla s k s were u sed , each w ith lOml o f b u ffe r a t pH 5,3 and two a t

pH 7«0t one a t each pH had 3ml ** glucose enzyme extract** and th e o th e r had 5ml **p e o ta te enzyme e x tr a c t" . The two l a s t ( o f th e 6) were given pH 7 ,0 and "g lu c o se - o r pec t a t e-en^rme e x tra c t" and were b o ile d in a double b o ile r f o r t h i r t y m inutes. These serv ed a s c o n tro ls .

To g et an id ea o f th e q u a n tity o f enzyme which was produced by th e fu n g i, 0,4mg o f commercial p e c tin a se (Signa London Chem, C o,) was d isso lv e d in 100ml

s t e r i l i z e d d i s t i l l e d w ater. U sing 4ml o f t h i s s o lu tio n lA ich co n ta in s 0,0l6m g p e c tin a s e , th e lo s s o f v is c o s ity

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