biostudies-literatureCai HNCRR NIH HHSNIAID NIH HHSNIGMS NIH HHS4180-7https://www.ebi.ac.uk/biostudies/studies/S-EPMC3758795biostudies-literatureUnknown61(17)The recombinant streptococcal protein apoShp can be used as a probe for hemoglobin (Hb) reactivity in fish muscle due to its specific affinity for hemin that is released from Hb at post-mortem pH values. Hemin affinity measurements indicated that apoShp binds hemin released from Hb but not myoglobin (Mb). Hemin affinity of holoShp was higher at pH 5.7 compared to pH 8.0. This may be attributed to enhanced electrostatic interaction of His58 with the heme-7-propionate at lower pH. ApoShp readily acquired hemin that was released from trout IV metHb in the presence of washed cod muscle during 2 °C storage at pH 6.3. This was based on increases in redness in the washed cod matrix, which occurs when apoShp binds hemin that is released from metHb. ApoShp prevented Hb-mediated lipid oxidation in wJournal of agricultural and food chemistryLipid oxidation in trout muscle is strongly inhibited by a protein that specifically binds hemin released from hemoglobin.PMC3758795GM103500-09P20 RR020185P20 GM103500R01 AI095704P30 GM110732Grunwald EWRichards MPPark SYLei BCai HfalseLipid oxidation in trout muscle is strongly inhibited by a protein that specifically binds hemin released from hemoglobin.The recombinant streptococcal protein apoShp can be used as a probe for hemoglobin (Hb) reactivity in fish muscle due to its specific affinity for hemin that is released from Hb at post-mortem pH values. Hemin affinity measurements indicated that apoShp binds hemin released from Hb but not myoglobin (Mb). Hemin affinity of holoShp was higher at pH 5.7 compared to pH 8.0. This may be attributed to enhanced electrostatic interaction of His58 with the heme-7-propionate at lower pH. ApoShp readily acquired hemin that was released from trout IV metHb in the presence of washed cod muscle during 2 °C storage at pH 6.3. This was based on increases in redness in the washed cod matrix, which occurs when apoShp binds hemin that is released from metHb. ApoShp prevented Hb-mediated lipid oxidation in w2013-01-01T00:00:00Z2013 May2025-04-26T11:05:08.106Z2019-03-27T01:15:21ZS-EPMC37587952357060810.1021/jf4006142