{"refrec":{"BRefID":281078,"RR":"<b>Shepherdley, C.A.; Richardson, S.J.; Evans, B.K.; Kühn, E.R.; Darras, V.M.</b> (2002). Characterization of outer ring iodothyronine deiodinases in tissues of the saltwater crocodile (<i>Crocodylus porosus</i>). <i>Gen. Comp. Endocrinol. 125(3)</i>: 387-398. <a href=\"https://dx.doi.org/10.1006/gcen.2001.7764\" target=\"_blank\">https://dx.doi.org/10.1006/gcen.2001.7764</a>","BEntID":273097,"PublicFlag":1,"CheckedFlag":1,"wosflag":1,"vabbflag":0,"RefStringPartII":". <i>Gen. Comp. Endocrinol. 125(3)</i>: 387-398. <a href=\"https://dx.doi.org/10.1006/gcen.2001.7764\" target=\"_blank\">https://dx.doi.org/10.1006/gcen.2001.7764</a>","DocTypID":8,"DocType":"Journal article","MarineFlag":1,"FreshFlag":0,"BrackishFlag":0,"TerrestrialFlag":0,"Authorstring":"Shepherdley, C.A.; Richardson, S.J.; Evans, B.K.; Kühn, E.R.; Darras, V.M.","OrigTitleTranslFlag":0,"Authorstringtrunc":"Shepherdley, C.A. <i>et al.</i>","Englishabstract":"The distribution and characterization of outer ring deiodination (ORD) using reverse triiodothyronine (rT<sub>3</sub>) and thyroxine (T<sub>4</sub>) as substrates is reported in microsomes of liver, kidney, lung, heart, gut, and brain tissues from juvenile saltwater crocodiles (<i>Crocodylus porosus</i>). In lung and heart only small amounts of rT<sub>3</sub> ORD and T<sub>4</sub> ORD were detected, while in brain only a small amount of T<sub>4</sub> ORD was detected. More detailed characterization studies could be performed on liver, kidney, and gut microsomes. Reverse T<sub>3</sub> outer ring deiodination (rT<sub>3</sub> ORD) was the predominant activity in liver and kidney microsomes. The properties of crocodile liver and kidney rT<sub>3</sub> ORD, such as preference for rT<sub>3</sub> as substrate, a dithiothreitol (DTT) requirement of 10 mM, inhibition by propylthiouracil (PTU), and Michaelis–Menten (<i>K</i><sub>m</sub>) constant in the micromolar range, correspond to the properties previously reported for a type I deiodinase. The temperature optimum for rT<sub>3</sub> ORD was between 30 and 35°. There was also rT<sub>3</sub> ORD activity in gut microsomes, along with what appeared to be a type II-like, low-<i>K</i><sub>m</sub> deiodinase with a substrate preference for T<sub>4</sub>. There was also a small amount of T<sub>4</sub> ORD activity in liver and kidney microsomes. Liver T<sub>4</sub> ORD, like a type II deiodinase, had a preference for T<sub>4</sub> as substrate at low substrate concentrations and a DTT requirement of 15 mM and was insensitive to PTU. However, at high substrate concentrations the predominant activity was of the type I deiodinase nature. T<sub>4</sub> ORD in liver had an optimal incubation temperature of 30 to 35°. Gut microsomal T<sub>4</sub> ORD was also type II-like at low substrate concentrations and type I-like at high substrate concentrations. Gut T<sub>4</sub> ORD had an optimal incubation temperature of 25 to 30° and a DTT requirement of 20 mM DTT. Kidney microsomal T<sub>4</sub> ORD had the same optimal temperature and DTT requirement as that in gut microsomes; however, there was no competition by low substrate concentrations. These results suggest that ORD in juvenile saltwater crocodile kidney is most likely exclusively catalyzed by a type I-like deiodinase. Liver and gut ORD, in contrast, is catalyzed by two enzymes, with a predominance of a type I-like deiodinase in liver and a type II-like deiodinase in gut. Low-<i>K</i><sub>m</sub> T<sub>3</sub> IRD activity could not be detected in any tissues of the juvenile saltwater crocodile.","AbstractOtherLang":null,"BibLvlCode":"AS","StandardTitle":"Characterization of outer ring iodothyronine deiodinases in tissues of the saltwater crocodile (<i>Crocodylus porosus</i>)","OrigTitleLangCode":"en","OrigTitleLangCodeExtended":"eng","OrigTitleLangID":15,"DateLastModified":{"date":"2026-06-15 01:32:57.425920","timezone_type":1,"timezone":"+02:00"},"UserAccessRight":null,"UserAccID":null,"AuthorKeywords":"deiodinases; thyroid hormones; saltwater crocodile","OtherDescriptors":null,"Notes":null,"AnaPub":2002,"MonPub":null,"DateUpdate":"2022-04-15","DateCreate":"2016-10-09","SecASFANote":null,"ConfID":null,"PeerRev":1,"VlizCoreFlag":1,"WoScode":"WOS:000174391300007","VABBcode":null,"OpenAcc":0,"DOI":"10.1006/gcen.2001.7764"},"refs":null,"anarec":{"AnaID":281078,"PubliDate":2002,"Pagination":"387-398","XtraPublOfAnaID":null,"ISBN":null,"Volume":"125","Issue":"3","BRefMon":null,"BRefMonRR":null,"BRefXtra":null,"BRefXtraRR":null,"SerBRefID":42729,"SerRR":"General and Comparative Endocrinology. Elsevier: New York,.  ISSN 0016-6480; e-ISSN 1095-6840","StandardTitleSer":"General and Comparative Endocrinology","ISSN":"0016-6480","AbbrevSer":"Gen. Comp. Endocrinol.","StandardTitleMon":null,"StartPage":387,"Pages":12,"ToPubliDate":null,"BRefBibLvlCode":"S","SerNotes":null},"monrec":null,"serrec":null,"relations":null,"relationsRev":null,"addrec":null,"othpubs":null,"ownerships":null,"authors":[{"AutName":"Shepherdley","Firstname":"Caroline","Initials":"C.A.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":273097,"AutID":243504,"OrderNr":1,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":null,"InsFSN":null,"ORCID":null,"PersID":null,"InsID":null},{"AutName":"Richardson","Firstname":"Samantha","Initials":"S.J.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":273097,"AutID":243505,"OrderNr":2,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":null,"InsFSN":null,"ORCID":null,"PersID":null,"InsID":null},{"AutName":"Evans","Firstname":"Barbara","Initials":"B.K.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":273097,"AutID":243506,"OrderNr":3,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":null,"InsFSN":null,"ORCID":null,"PersID":null,"InsID":null},{"AutName":"Kühn","Firstname":"Eduard","Initials":"E.R.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":273097,"AutID":3110,"OrderNr":4,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":null,"InsFSN":null,"ORCID":null,"PersID":null,"InsID":null},{"AutName":"Darras","Firstname":"Veerle","Initials":"V.M.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":273097,"AutID":3108,"OrderNr":5,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":null,"InsFSN":null,"ORCID":null,"PersID":null,"InsID":null}],"mapdetails":null,"datasets":null,"monographs":null,"monparts":null,"serparts":null,"BEntOpen":null,"BEntPrivate":null,"availability":[{"BInstID":375694,"LibID":36,"BRefID":281078,"EmbargoDate":null,"FullEmbargoDate":null,"PhysMedID":16,"hasOCRd":null,"ShelfLocCode":"375694","RFID":null,"PaidValue":null,"Medium":"Server","Description":"Interne VLIZ documenten","Acronym":"VLIZ","Library":"Vlaams Instituut voor de Zee","DutchTerm":"Non-open access","URL":null,"ClassifID":228,"Classification":"Non-open access","ReqLink":1,"ClassifTypID":3,"URLLocation":"https://www.vliz.be/imisdocs/publications/","SubDir":1,"InternalReq":1,"LoggedInReq":1,"Disclaimer":"Disclaimer_VLIZ_Intern","DutchDisclaimer":"<p>Deze publicatie is enkel beschikbaar voor persoonlijk gebruik binnen de Innovocean site <br />en mag op geen enkele manier verder worden verspreid.</p>","FileFormat":".pdf","FileDescr":"pdf","InsPub":1,"InsID":36,"FileFormID":6,"LendableFlag":1,"PublicFlag":1,"orderLib":"A","Notes":null,"AccConID":null,"AccessConstraint":null,"LicURL":null}],"litstyles":null,"thespers":null,"arch2discl":null,"SERpubls":[{"PublName":"Elsevier","City":"New York,"}],"MONpubls":null,"pictures":[],"thestermsPath":null,"thestermsASFA":null,"taxtermsASFA":[{"TaxTerm":"Crocodylus porosus"}],"geotermsASFA":null,"collections":null,"conf":null,"proj":null,"Physdatasets":null,"spcols":{"222":{"SpName":"BMB - Belgische Mariene Bibliografie","SpColID":222,"ParSpColID":null,"TopParID":null,"ShortName":"BMB","URLLocation":null,"LibID":36,"OpenRepoFlag":null,"SpTypID":null,"TopParIDNotWebsite":null,"SpColPath":"BMB"}},"doi":null,"publs":null,"serparttypes":null,"monauthors":null,"MParts":null,"SParts":null,"hLibs":null,"langs":[{"BEntID":273097,"AbstractFlag":0,"LangID":15,"LangCode":"en","Lang":"English","DutchTerm":"Engels","LangCodeExtended":"eng"},{"BEntID":273097,"AbstractFlag":1,"LangID":15,"LangCode":"en","Lang":"English","DutchTerm":"Engels","LangCodeExtended":"eng"}],"urls":[{"URL":"https://dx.doi.org/10.1006/gcen.2001.7764","externalID":"10.1006/gcen.2001.7764","URLTypeCode":"DOI","URLID":51392,"URLTypID":13,"URLType":"DOI","URLPrefix":"http://dx.doi.org/"}],"thesterms":null,"taxterms":[{"TaxTerm":"Crocodylus porosus","AphiaID":344030,"TaxtID":42583}],"geoterms":null,"othterms":null,"asfacodes":null,"asfa2codes":null,"thestermsFRIS":null,"taxtermsFRIS":[{"TaxTerm":"Crocodylus porosus","DutchTerm":null,"AphiaID":344030,"TaxtID":42583}],"geotermsFRIS":null,"othtermsFRIS":null,"resmessage":"","complete":1,"sessions":{"newSesName":"Lyssens, Liesbeth, L.","newSesDate":{"date":"2016-10-09 21:20:26.960000","timezone_type":3,"timezone":"Europe/Brussels"},"updSesName":"Bouchti, Zohra, Z.","updSesDate":{"date":"2022-04-15 08:15:31.570000","timezone_type":3,"timezone":"Europe/Brussels"}}}