Thiol dioxygenases: unique families of cupin proteins.
Thiol dioxygenases: unique families of cupin proteins.
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DOI：
10.1007/s00726-010-0518-2
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发表时间：
2011-06
期刊：
影响因子：
3.5
通讯作者：
Dominy, John E., Jr.
中科院分区：
文献类型：
--
作者：
Stipanuk, Martha H.;Simmons, Chad R.;Karplus, P. Andrew;Dominy, John E., Jr.
关键词：
Cupin超家族蛋白在古生物、细菌和真核生物中具有广泛的生物学功能。尽管Cupin超家族的蛋白质总体序列相似性很低，但它们都包含两个短的但部分保守的Cupin序列基序，由一个不太保守的基序间区分隔，该基序区域的长度和氨基酸序列都不同。此外，这些蛋白质都有一个被描述为6链β-桶核心的共同结构，并且这个典型的β-桶是由Cupin基序1、基序间区和Cupin基序2形成的，每个Cupin基序2都形成了折叠蛋白质结构中的核心6条β-链中的两条。最近获得的半胱氨酸双加氧酶的晶体结构表明，它具有典型的Cupinβ-Barrel折叠，含有保守的Cupin基序。虽然在原核生物中还没有关于CDO活性的报道，但我们发现了一些功能未知的细菌Cupin蛋白，它们与哺乳动物CDO的相似性很低，并且在CDO的活性部位口袋中保存了许多残基。推测具有CDO活性的细菌CDO与真核CDO具有相似的底物特异性和动力学参数。从哺乳动物CDO的晶体结构中收集的信息以及具有CDO活性的同源物的序列信息有助于识别CDO家族指纹基序。CDO指纹基序的一个关键特征是Cupin基序1中典型的金属结合谷氨酸残基被半胱氨酸(在哺乳动物CDO中)或甘氨酸(细菌CDO)所取代。最近有报道称，一些假定的细菌CDO同源物实际上是3-巯基丙酸双加氧酶，这表明CDO家族可能包括具有其他硫醇底物特异性的蛋白质。在哺乳动物中也发现了一个与CDO类似的酶，证明它是另一种哺乳动物的硫醇双加氧酶，半胱胺双加氧酶(ADO)。提出了一种针对ADO或DUF1637家族成员的暂定指纹图案。在ADOS中，Cupin基序1中保守的谷氨酸残基被甘氨酸或Valine取代。ADO和CDO似乎都代表了Cupin超家族中的独特分支。
Proteins in the cupin superfamily have a wide range of biological functions in archaea, bacteria and eukaryotes. Although proteins in the cupin superfamily show very low overall sequence similarity, they all contain two short but partially conserved cupin sequence motifs separated by a less conserved intermotif region that varies both in length and amino acid sequence. Furthermore, these proteins all share a common architecture described as a 6-stranded β-barrel core, and this canonical cupin or “jelly roll” β-barrel is formed with cupin motif 1, the intermotif region, and cupin motif 2 each forming two of the core six β-strands in the folded protein structure. The recently obtained crystal structures of cysteine dioxygenase (CDO), with contains conserved cupin motifs, show that it has the predicted canonical cupin β-barrel fold. Although there had been no reports of CDO activity in prokaryotes, we identified a number of bacterial cupin proteins of unknown function that share low similarity with mammalian CDO and that conserve many residues in the active site pocket of CDO. Putative bacterial CDOs predicted to have CDO activity were shown to have similar substrate specificity and kinetic parameters as eukaryotic CDOs. Information gleaned from crystal structures of mammalian CDO along with sequence information for homologs shown to have CDO activity facilitated the identification of a CDO family fingerprint motif. One key feature of the CDO fingerprint motif is that the canonical metal-binding glutamate residue in cupin motif 1 is replaced by a cysteine (in mammalian CDOs) or by a glycine (bacterial CDOs). The recent report that some putative bacterial CDO homologs are actually 3-mercaptopropionate dioxygenases suggests that the CDO family may include proteins with specificities for other thiol substrates. A paralog of CDO in mammals was also identified and shown to be the other mammalian thiol dioxygenase, cysteamine dioxygenase (ADO). A tentative fingerprint motif for ADOs, or DUF1637 family members, is proposed. In ADOs, the conserved glutamate residue in cupin motif 1 is replaced by either glycine or valine. Both ADOs and CDOs appear to represent unique clades within the cupin superfamily.
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影响因子：
2.9
作者：
Rogers, Melanie S.;Hurtado-Guerrero, Ramon;McPherson, Michael J.
通讯作者：
McPherson, Michael J.
影响因子：
15
作者：
Rogers, MS;Baron, AJ;Dooley, DM
通讯作者：
Dooley, DM
DOI：
10.1107/s0907444900002237
发表时间：
2000-04-01
影响因子：
2.2
作者：
Ko, TP;Day, J;McPherson, A
通讯作者：
McPherson, A
DOI：
10.1016/0005-2744(76)90138-8
发表时间：
1976-01-01
期刊：
BIOCHIMICA ET BIOPHYSICA ACTA
影响因子：
--
作者：
SAKAKIBARA, S;YAMAGUCHI, K;SAKAMOTO, Y
通讯作者：
SAKAMOTO, Y
影响因子：
15
作者：
Aluri, Swathi;de Visser, Sam P.
通讯作者：
de Visser, Sam P.