A mannan binding lectin is involved in cell-cell attachment in a toxic strain of Microcystis aeruginosa
A mannan binding lectin is involved in cell-cell attachment in a toxic strain of Microcystis aeruginosa
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DOI：
10.1111/j.1365-2958.2005.05001.x
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发表时间：
2006-02-01
影响因子：
3.6
通讯作者：
Dittmann, E
中科院分区：
文献类型：
--
作者：
Kehr, JC;Zilliges, Y;Dittmann, E
微囊藻毒素是一种肝毒素，对人类和牲畜的健康有严重的危害，是由全球淡水水体中的水华蓝藻铜绿微囊藻产生的。在这里，我们描述了一个凝集素，微病毒蛋白（MVN），在M。铜绿假单胞菌PCC 7806与来自椭圆孢念珠藻的有效抗HIV蛋白氰毒蛋白-N具有33%的同一性。碳水化合物微阵列用于证明蛋白质对含有α（1 -> 2）连接的甘露糖残基的高甘露糖结构的高特异性。凝集素结合分析和MVN缺陷突变体的表型特征表明，MVN参与微囊藻的细胞-细胞识别和细胞-细胞附着。在M的脂多糖组分中鉴定了MVN的结合伴侣。铜绿假单胞菌PCC 7806。MVN在缺乏肝毒素微囊藻毒素的突变体中差异表达。此外，MVN缺陷型突变体含有比野生型细胞低得多的微囊藻毒素。我们讨论了微囊藻毒素和凝集素之间可能的功能相关性和可能的影响微囊藻形态形成。这项研究提供了第一个实验证据表明，微囊藻毒素可能会对微囊藻群落的形成，这是非常重要的竞争优势，微囊藻超过其他浮游植物物种的影响。
Microcystin, a hepatotoxin that represents a serious health risk for humans and livestock, is produced by the bloom-forming cyanobacterium Microcystis aeruginosa in freshwater bodies worldwide. Here we describe the discovery of a lectin, microvirin (MVN), in M. aeruginosa PCC7806 that shares 33% identity with the potent anti-HIV protein cyanovirin-N from Nostoc ellipsosporum. Carbohydrate microarrays were employed to demonstrate the high specificity of the protein for high-mannose structures containing alpha(1 -> 2) linked mannose residues. Lectin binding analyses and phenotypic characterizations of MVN-deficient mutants suggest that MVN is involved in cell-cell recognition and cell-cell attachment of Microcystis. A binding partner of MVN was identified in the lipopolysaccharide fraction of M. aeruginosa PCC7806. MVN is differentially expressed in mutants lacking the hepatotoxin microcystin. Additionally, MVN-deficient mutants contain much lower amounts of microcystin than the wild-type cells. We discuss a possible functional correlation between microcystin and the lectin and possible implications on Microcystis morphotype formation. This study provides the first experimental evidence that microcystins may have an impact on Microcystis colony formation that is highly important for the competitive advantage of Microcystis over other phytoplankton species.