title: Altered AMP deaminase activity may extend postmortem glycolysis.
abstract: Postmortem energy metabolism drives hydrogen accumulation in muscle and results in a fairly constant ultimate pH. Extended glycolysis results in adverse pork quality and may be possible with greater adenonucleotide availability postmortem. We hypothesized that slowing adenonucleotide removal by reducing AMP deaminase activity would extend glycolysis and lower the ultimate pH of muscle. Longissimus muscle samples were incorporated into an in vitro system that mimics postmortem glycolysis with or without pentostatin, an AMP deaminase inhibitor. Pentostatin lowered ultimate pH and increased lactate and glucose 6-phosphate with time. Based on these results and that AMPK γ3(R200Q) mutated pigs (RN⁻) produce low ultimate pH pork, we hypothesized AMP deaminase abundance and activity would be lower in RN⁻ muscle than wild-type. RN⁻ muscle contained lower AMP deaminase abundance and activity. These data show that altering adenonucleotide availability postmortem can extend postmortem pH decline and suggest that AMP deaminase activity may, in part, contribute to the low ultimate pH observed in RN⁻ pork.
authors.affiliation: Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
authors.forename: E M
authors.initials: EM
authors.lastname: England
authors.affiliation: Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
authors.forename: S K
authors.initials: SK
authors.lastname: Matarneh
authors.affiliation: Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
authors.forename: T L
authors.initials: TL
authors.lastname: Scheffler
authors.affiliation: Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
authors.forename: C
authors.initials: C
authors.lastname: Wachet
authors.affiliation: Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA. Electronic address: dgerrard@vt.edu.
authors.forename: D E
authors.initials: DE
authors.lastname: Gerrard
mesh_terms: D000659:AMP Deaminase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D058892:Adenosine Deaminase Inhibitors / Q000494:pharmacology; D019943:Amino Acid Substitution; D000818:Animals; D017849:Animals, Inbred Strains; D063427:Food Quality; D061353:Food Storage; D006019:Glycolysis / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D008460:Meat / Q000032:analysis*; D018482:Muscle, Skeletal / Q000737:chemistry / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D009154:Mutation; D015649:Pentostatin / Q000494:pharmacology; D020641:Polymorphism, Single Nucleotide; D021122:Protein Subunits; D034421:Sus scrofa; D014768:Virginia
chemical_list: D058892:Adenosine Deaminase Inhibitors; D021122:Protein Subunits; D015649:Pentostatin; D000659:AMP Deaminase
keywords: AMP deaminase; Glycolysis; Pork; Rendement Napole