A comparison of methanobactins from Methylosinus trichosporium OB3b and Methylocystis strain Sb2 predicts methanobactins are synthesized from diverse peptide precursors modified to create a common core for binding and reducing copper ions.
A comparison of methanobactins from Methylosinus trichosporium OB3b and Methylocystis strain Sb2 predicts methanobactins are synthesized from diverse peptide precursors modified to create a common core for binding and reducing copper ions.
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从甲基孢子菌素OB3b和甲基囊肿菌株SB2中的甲烷素的比较预测甲烷酰胺是由经过修饰的各种肽前体合成的，以创建一种用于结合和还原铜离子的共同核心。
DOI：
10.1021/bi1014375
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发表时间：
2010-11-30
期刊：
影响因子：
2.9
通讯作者：
Gallagher, Warren H.
中科院分区：
文献类型：
--
作者：
Krentz, Benjamin D.;Mulheron, Heidi J.;Semrau, Jeremy D.;DiSpirito, Alan A.;Bandow, Nathan L.;Haft, Daniel H.;Vuilleumier, Stephane;Murrell, J. Colin;McEllistrem, Marcus T.;Hartsel, Scott C.;Gallagher, Warren H.
甲烷结合蛋白(Mb)是大多数甲烷氧化细菌分泌的低分子量铜结合分子。这些分子已被鉴定为许多甲烷氧化菌，但到目前为止，只有一种由甲氧西林天花粉OB3b(mb-OB3b)产生的分子被化学表征。在这里，我们报道了第二种甲氧基丁酸菌素(mb-sb2)的化学特性和铜结合性能。MB-SB2与MB-OB3b有一些显著的相似之处，包括它的光谱和金属结合性质，以及它结合和还原铜(II)到铜(I)的能力。与mb-OB3b一样，mb-SB2含有两个五元杂环及其相关的烯硫醇基团，它们共同形成铜离子结合部位。与MB-OB3b相比，MB-SB2还表现出一些显著的差异，包括用于完成分子结构的氨基酸的数量和类型、在MB-OB3b中发现的取代其中一个恶唑酮环的咪唑酮环的存在以及在MB-OB3b中没有的硫酸盐基团的存在。硫酸盐与苏氨酸样侧链键合，该苏氨酸侧链与杂环环之一相关联，并且可以代表在细菌衍生的多肽中发现的这种类型的硫酸盐基团的第一个例子。Mb-OB3b和mb-SB2中的恶唑酮环在酸催化下的水解和脱羧化产生了一对氨基酸残基，这表明mb-OB3b和mb-SB2都是多肽的产物。为了支持这一点，已经在毛霉菌OB3b的基因组中鉴定了mb-OB3b的核糖体产生的多肽前体基因。该基因序列表明，mb-OB3b中的恶唑酮环是半胱氨酸残基和多肽序列中前一个残基的羰基结合而成的。综上所述，这些结果表明，甲烷结合蛋白组成了一组结构多样化的核糖体产生的多肽分子，它们与相关的烯硫醇基团共享一对共同的五元环，能够在水环境中结合、还原和稳定铜离子。
Methanobactins (mb) are low-molecular mass, copper-binding molecules secreted by most methanotrophic bacteria. These molecules have been identified for a number of methanotrophs, but only the one produced by Methylosinus trichosporium OB3b (mb-OB3b) has to date been chemically characterized. Here we report the chemical characterization and copper binding properties of a second methanobactin, which is produced by Methylocystis strain SB2 (mb-SB2). mb-SB2 shows some significant similarities to mb-OB3b, including its spectral and metal binding properties, and its ability to bind and reduce Cu(II) to Cu(I). Like mb-OB3b, mb-SB2 contains two five-member heterocyclic rings with associated enethiol groups, which together form the copper ion binding site. mb-SB2 also displays some significant differences compared to mb-OB3b, including the number and types of amino acids used to complete the structure of the molecule, the presence of an imidazolone ring in place of one of the oxazolone rings found in mb-OB3b, and the presence of a sulfate group not found in mb-OB3b. The sulfate is bonded to a threonine-like side chain that is associated with one of the heterocyclic rings and may represent the first example of this type of sulfate group found in a bacterially derived peptide. Acid-catalyzed hydrolysis and decarboxylation of the oxazolone rings found in mb-OB3b and mb-SB2 produce pairs of amino acid residues and suggest that both mb-OB3b and mb-SB2 are derived from peptides. In support of this, the gene for a ribosomally produced peptide precursor for mb-OB3b has been identified in the genome of M. trichosporium OB3b. The gene sequence indicates that the oxazolone rings in mb-OB3b are derived from the combination of a cysteine residue and the carbonyl from the preceding residue in the peptide sequence. Taken together, the results suggest methanobactins make up a structurally diverse group of ribosomally produced, peptide-derived molecules, which share a common pair of five-member rings with associated enethiol groups that are able to bind, reduce, and stabilize copper ions in an aqueous environment.
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影响因子：
15
作者：
Li, H;Webb, SP;Jensen, JH
通讯作者：
Jensen, JH
影响因子：
3.9
作者：
Choi, Dong W.;Bandow, Nathan L.;DiSpirito, Alan A.
通讯作者：
DiSpirito, Alan A.
影响因子：
15
作者：
Hakemian, AS;Tinberg, CE;Rosenzweig, AC
通讯作者：
Rosenzweig, AC
影响因子：
15
作者：
Martinho, Marlene;Choi, Dong W.;Muenck, Eckard
通讯作者：
Muenck, Eckard
影响因子：
1.5
作者：
Kremer, Mordechai L.
通讯作者：
Kremer, Mordechai L.