Redox Instability Induced by 4-Hydroxy-2-nonenal in Porcine and Bovine Myoglobins at pH 5.6 and 4 °C

Abstract

Myoglobin (Mb) redox stability affects meat color and is compromised by lipid oxidation products such as 4-hydroxy-2-nonenal (HNE). Pork lipids are generally more unsaturated and would be expected to oxidize readily and produce more oxidation products than beef. Supranutritional supplementation of vitamin E improves Mb redox stability of beef but not pork. The present study investigated HNE-induced redox instability in porcine and bovine myoglobins at 4 degrees C and pH 5.6. Oxymyoglobin (OxyMb) was incubated with HNE (0.075 mM porcine OxyMb + 0.5 mM HNE; 0.15 mM bovine OxyMb + 1.0 mM HNE). In porcine Mb, only monoadducts formed via Michael addition were detected after 72 h, whereas in bovine Mb both mono- and diadducts were identified. LC-MS-MS identified four histidine residues (His 36, 81, 88, and 152) of bovine Mb that were readily adducted by HNE, whereas in porcine Mb only two histidine residues (His 24 and 36) were adducted. These results suggested that the primary structure of bovine Mb predisposes it to greater nucleophilic attack by HNE and subsequent adduction than is suffered by porcine Mb.

Application of proteomics to characterize and improve color and oxidative stability of muscle foods

“…HNE is an α, β-unsaturated aldehyde, generated by the oxidation of ω-6 polyunsaturated fatty acids in the biological membranes (Schneider, Tallman, Porter, & Brash, 2001). The prooxidative effect of HNE has been reported in different Mb species, such as tuna (Lee, Joo, Alderton, Hill, & Faustman, 2003), pork (Lee, Phillips, Liebler, & Faustman, 2003;Suman, Faustman, Stamer, & Liebler, 2006, horse (Faustman, Liebler, McClure, & Sun, 1999) and beef (Alderton, Faustman, Liebler, & Hill, 2003;Suman et al, 2007). Molecular basis of lipid oxidation-induced Mb oxidation has been investigated extensively using MS and proteomic tools.…”

“…Molecular basis of lipid oxidation-induced Mb oxidation has been investigated extensively using MS and proteomic tools. Covalent modification of amino acids via aldehyde adduction was concluded as the reason for lipid oxidation-induced Mb oxidation (Faustman et al, 1999;Alderton et al, 2003;Lee, Phillips, et al, 2003;Suman et al, 2006Suman et al, , 2007. Cysteine, lysine, arginine and histidine are the most susceptible amino acids for nucleophilic attack by HNE for Michael addition (Bolgar & Gaskell, 1996;Isom et al, 2004;Uchida & Stadtman, 1992).…”

“…However, cysteine residues are absent in livestock Mbs (Livingston & Brown, 1981). Mass spectrometry-based proteomic investigations demonstrated that HNE adduction occurred exclusively at histidine residues in livestock Mb Lee, Phillips, et al, 2003;Suman et al, 2006Suman et al, , 2007. HNE adduction at histidine residues, more specifically at HIS 64 (distal histidine) and HIS 93 (proximal histidine), which co-ordinate the heme group in Mb, destabilizes heme iron's ability to bind with oxygen and thus, compromise Mb redox stability.…”

Modified Atmosphere Packaging Improves Surface Color of Dark-Cutting Beef

“…can be attributed to the protective effect of pH on oxymyoglobin and lipid oxidation. In-vitro experiments utilizing purified myoglobin also demonstrated greater stability of oxymyoglobin at pH 7.4 than at pH 5.6 (Suman et al, 2006). Previous research also reported lower TBARS values in dark-cutting beef than normal-pH steaks (Sawyer et al, 2009).…”

Primary structure of turkey myoglobin

“…On the other hand, differences in the amino acid sequence influence the interaction between myoglobin and lipid oxidation products. Beef myoglobin was more susceptible to lipid oxidation-induced oxidation than was pork myoglobin (Suman, Faustman, Stamer, & Liebler, 2006). Further investigations (Suman, Faustman, Stamer, & Liebler, 2007) suggested preferential adduction of aldehydes at the proximal histidine residue (position 93) in beef myoglobin as a reason for the increased propensity of beef myoglobin to undergo lipid oxidation-induced oxidation.…”