Cytoglobin (Histoglobin) (HGb) (Stellate cell activation-associated protein)
1_MEKVP 6_ GEMEI 11_ ERRER 16_ SEELS 21_ EAERK 26_ AVQAM 31_ WARLY 36_ ANCED 41_ VGVAI 46_ LVRFF 51_ VNFPS 56_ AKQYF 61_ SQFKH 66_ MEDPL 71_ EMERS 76_ PQLRK 81_ HACRV 86_ MGALN 91_ TVVEN 96_ LHDPD 101_ KVSSV 106_ LALVG 111_ KAHAL 116_ KHKVE 121_ PVYFK 126_ ILSGV 131_ ILEVV 136_ AEEFA 141_ SDFPP 146_ ETQRA 151_ WAKLR 156_ GLIYS 161_ HVTAA 166_ YKEVG 171_ WVQQV 176_ PNATT 181_PPATL
1: Probable multifunctional globin with a hexacoordinated heme iron required for the catalysis of various reactions depending on redox condition of the cell as well as oxygen availability (PubMed:11893755, PubMed:12359339, PubMed:15165856, PubMed:19147491, PubMed:20511233, PubMed:28393874, PubMed:28671819, PubMed:29128400, PubMed:33576020, PubMed:34930834). Has a nitric oxide dioxygenase (NOD) activity and is most probably involved in cell-mediated and oxygen-dependent nitric oxide consumption (PubMed:19147491, PubMed:20511233, PubMed:28393874, PubMed:28671819). By scavenging this second messenger may regulate several biological processes including endothelium-mediated vasodilation and vascular tone (PubMed:19147491, PubMed:28393874). Under normoxic conditions functions as a nitric oxide dioxygenase (NOD) but under hypoxic conditions the globin may switch its function to that of a nitrite (NO2) reductase (NiR), generating nitric oxide (PubMed:29128400). Could also have peroxidase and superoxide dismutase activities, detoxifying reactive oxygen species and protecting cells against oxidative stress (PubMed:12359339, PubMed:33576020, PubMed:34930834). Also binds dioxygen with low affinity and could function as an oxygen sensor but has probably no function as a respiratory oxygen carrier (PubMed:11893755, PubMed:15299006, PubMed:20553503)