The initial kinetics of NH3/NH4+ efflux from L3Teladorsagia circumcincta

Muhamad, Noorzaid, Walker, Lisa R., Pedley, Kevin C., Simcock, David C., and Brown, Simon (2012) The initial kinetics of NH3/NH4+ efflux from L3Teladorsagia circumcincta. Parasitology International, 61 (3). pp. 487-492.

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The initial rate of NH3/NH4+ accumulation in a medium containing L3Teladorsagia circumcincta was 0.18–0.6 pmol h− 1 larva− 1, which increased linearly with larval density. However it appeared that the larva-generated external concentration of NH3/NH4+ did not exceed about 130 μM. The rate of NH3/NH4+ accumulation increased with temperature between 4 °C and 37 °C, declined with increasing pH or increasing external NH3/NH4+ concentration and was not significantly affected by the concentration of the phosphate buffer or by exsheathing the larvae. We infer from these data that the efflux of NH3/NH4+ is a diffusive process and that the secreted or excreted NH3/NH4+ is generated enzymatically rather than dissociating from the surface of the nematode. The enzymatic source of the NH3/NH4+ is yet to be identified. Since the concentration of NH3/NH4+ in the rumen and abomasum is higher than 130 μM, it is unlikely that T. circumcincta contributes to it, but NH3/NH4+ may be accumulated from the rumen fluid by the nematode.

Item ID: 35751
Item Type: Article (Research - C1)
ISSN: 1873-0329
Keywords: Teladorsagia circumcincta, parasite, ammonia, diffusion, kinetics
Funders: Beef and Lamb New Zealand, Agricultural and Marketing Research and Development Trust (AGMARDT), Universiti Malaysia Sarawak, Public Service Department (Malaysia)
Date Deposited: 15 Oct 2014 16:48
FoR Codes: 06 BIOLOGICAL SCIENCES > 0601 Biochemistry and Cell Biology > 060104 Cell Metabolism @ 50%
07 AGRICULTURAL AND VETERINARY SCIENCES > 0707 Veterinary Sciences > 070708 Veterinary Parasitology @ 50%
SEO Codes: 97 EXPANDING KNOWLEDGE > 970106 Expanding Knowledge in the Biological Sciences @ 50%
97 EXPANDING KNOWLEDGE > 970107 Expanding Knowledge in the Agricultural and Veterinary Sciences @ 50%
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