A Study on Esterase Activity of Carbonic Anhydrase from Van Lake Fish (Calcalburnus tarichi)

Haluk TESTERECİ

Article Details

A Study on Esterase Activity of Carbonic Anhydrase from Van Lake Fish (Calcalburnus tarichi)

Authors:

Haluk TESTERECİ

Publisher:

TUBITAK

Journal:

Turkish Journal of Veterinary and Animal Sciences 1999 Vol.23 Issue EK1, pp.145-154

Document Type:

Article

Publication Date:

11/1998

Document Language:

Turkish

Document ID (Org No.):

2000772393

Frequency:

Bimonthly

eISSN:

1303-6181

pISSN:

1300-0128

Keywords:

Abstract:

 

No study has been reported on carbonic anhydrase enzyme of the  fish (Calcalburnus tarichi) living in the carbonated Van Lake. Having partial purification of  Carbonic anhydrase from gill and liver of Van Lake fish  by ethanol-chloroform and acetone-chloroform, the esterase activity was performed by using p-nitrophenyl acetate as a substrate on spectrophotometer. The effects of  the some kinetic parameters (km, Vo, Vmax, Na2CO3 activation, optimum pH etc.) have been examined      When Lineweaver-Burk diagram of liver extracts (at 25°C) is examined, ethanol has an apparent  competitive inhibition compare to acetone extracts. So Km of the substrate (p-nitrophenyl acetate)  is 0.95 mM is for ethanol extract and 0.54 mM of that is found for acetone extracts. In two extracts from gill (at 25°C),  ethanol seems to have a non-competitive inhibition comparing to acetone, Km for both extracts is 0.39 mM.  Na+/CO32-  ions induce esterase activity, Na+/CO3-2 ions are not competitive with the inhibitory effects of ethanol.  Infect,  inhibition of ethanol on gill  esterase activity appears to be competitive which is understood  by addition of Na+/CO3-2.  Since carbonate ions and p-nitrophenyl acetate  act on two different catalytic site of this enzyme, both have formed a cooperative effect  It is clear that carbonic anhydrase activity has not been affected till pH:7.4. Although pH above 8.0 enzyme activity has seem to increase, this increase is due to kinetic reaction between substrate (p-nitropheny acetate) and  buffer at pH:8-11.5. So, the esterase activity of this enzyme at this high pH, can not be evaluated. for the esterase activity of this enzyme. The optimal and unaffected pH for the substrate is 7 for the esterase activity of carbonic anhydrase.  "Esterase" activity could be useful for determining "anhydrase" activity of Carbonic anhydrase enzyme of Van Lake fish.  Stimulation of esterase activity of carbonic anhydrase has been shown by addition of CO32- ions.  Carbonic anhydrase present in gill and liver of Van Lake fish has a significant regulatory role for internal  pH balance.

 

No study has been reported on carbonic anhydrase enzyme of the  fish (Calcalburnus tarichi) living in the carbonated Van Lake. Having partial purification of  Carbonic anhydrase from gill and liver of Van Lake fish  by ethanol-chloroform and acetone-chloroform, the esterase activity was performed by using p-nitrophenyl acetate as a substrate on spectrophotometer. The effects of  the some kinetic parameters (km, Vo, Vmax, Na2CO3 activation, optimum pH etc.) have been examined      When Lineweaver-Burk diagram of liver extracts (at 25°C) is examined, ethanol has an apparent  competitive inhibition compare to acetone extracts. So Km of the substrate (p-nitrophenyl acetate)  is 0.95 mM is for ethanol extract and 0.54 mM of that is found for acetone extracts. In two extracts from gill (at 25°C),  ethanol seems to have a non-competitive inhibition comparing to acetone, Km for both extracts is 0.39 mM.  Na+/CO32-  ions induce esterase activity, Na+/CO3-2 ions are not competitive with the inhibitory effects of ethanol.  Infect,  inhibition of ethanol on gill  esterase activity appears to be competitive which is understood  by addition of Na+/CO3-2.  Since carbonate ions and p-nitrophenyl acetate  act on two different catalytic site of this enzyme, both have formed a cooperative effect  It is clear that carbonic anhydrase activity has not been affected till pH:7.4. Although pH above 8.0 enzyme activity has seem to increase, this increase is due to kinetic reaction between substrate (p-nitropheny acetate) and  buffer at pH:8-11.5. So, the esterase activity of this enzyme at this high pH, can not be evaluated. for the esterase activity of this enzyme. The optimal and unaffected pH for the substrate is 7 for the esterase activity of carbonic anhydrase.  "Esterase" activity could be useful for determining "anhydrase" activity of Carbonic anhydrase enzyme of Van Lake fish.  Stimulation of esterase activity of carbonic anhydrase has been shown by addition of CO32- ions.  Carbonic anhydrase present in gill and liver of Van Lake fish has a significant regulatory role for internal  pH balance.

Article Details

A Study on Esterase Activity of Carbonic Anhydrase from Van Lake Fish (Calcalburnus tarichi)

Authors: Haluk TESTERECİ

Publisher: TUBITAK

Journal: Turkish Journal of Veterinary and Animal Sciences 1999 Vol.23 Issue EK1, pp.145-154

Document Type: Article

Publication Date: 11/1998

Document Language: Turkish

Document ID (Org No.): 2000772393

Frequency: Bimonthly

eISSN: 1303-6181

pISSN: 1300-0128

Carbonic anhydrase

Van Lake fish

esterase activity

Issues

Authors:

Haluk TESTERECİ

Publisher:

TUBITAK

Journal:

Turkish Journal of Veterinary and Animal Sciences 1999 Vol.23 Issue EK1, pp.145-154

Document Type:

Article

Publication Date:

11/1998

Document Language:

Turkish

Document ID (Org No.):

2000772393

Frequency:

Bimonthly

eISSN:

1303-6181

pISSN:

1300-0128