| Title: |
Urea output by L3 Teladorsagia circumcincta and some properties of two urea producing enzymes |
| Authors: |
Muhamad, N; Walker, LR; Simcock, DC; Pedley, KC; Simpson, HV; Brown, SG |
| Publication Year: |
2013 |
| Subject Terms: |
Medical parasitology; kinetics; Teladorsagia circumcincta; urea |
| Description: |
Background: Like several other parasites, Teladorsagia circumcincta secretes or excretes urea, but neither the rate of efflux nor the possible metabolic sources of the urea has been considered. Methods: Parasites were maintained by passage through sheep. Urea efflux was measured using phenol/hypochlorite after treatment with urea aminohydrolase. The kinetics of creatine amidinohydrolase and arginine amidinohydrolase were characterised by coupling the reactions with urea aminohydrolase and glutamate dehydrogenase. Results: Infective L3 T. circumcincta secreted or excreted urea at 25% of the rate of NH 3 /NH 4 + . The rate of urea efflux was about 84 pmol h -1 (103 larvae) -1 over 4 hours, corresponding to about 11 nmol h -1 mg -1 protein. We could not detect urea aminohydrolase activity, but urea production by both creatine amidinohydrolase and arginine amidinohydrolase could be detected. The apparent K m and V max of creatine amidinohydrolase were 1.1 mM and 48 nmol h -1 mg -1 protein, respectively, and the activity was greatest at pH 8. The apparent K m and V max of arginine amidinohydrolase were 0.7 mM and 62 nmol h -1 mg -1 protein, respectively, and the activity was greatest at pH 7.9. Conclusion: The activity of creatine amidinohydrolase and arginine amidinohydrolase was sufficient to account for the rate of urea secretion or excretion. |
| Document Type: |
article in journal/newspaper |
| Language: |
unknown |
| Relation: |
102.100.100/576735; https://figshare.com/articles/journal_contribution/Urea_output_by_L3_Teladorsagia_circumcincta_and_some_properties_of_two_urea_producing_enzymes/22911425 |
| Availability: |
https://figshare.com/articles/journal_contribution/Urea_output_by_L3_Teladorsagia_circumcincta_and_some_properties_of_two_urea_producing_enzymes/22911425 |
| Rights: |
In Copyright |
| Accession Number: |
edsbas.C3E7E49B |
| Database: |
BASE |