Structure, biological activity and membrane partitioning of analogs of the isoprenylated a-factor mating peptide of Saccharomyces cerevisiae.
Structure, biological activity and membrane partitioning of analogs of the isoprenylated a-factor mating peptide of Saccharomyces cerevisiae.
复制标题
酿酒酵母异戊二烯化 a 因子交配肽类似物的结构、生物活性和膜分配。
DOI：
10.1034/j.1399-3011.2000.00705.x
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Naider,F
中科院分区：
文献类型：
--
作者：
Xie,H;Becker,JM;Gibbs,RA;Naider,F
先前对酿酒酵母因子的生化研究表明，该脂肽信息素[YIIKGVFWDPAC(farnesyl)OMe]可能在肽序列的第4位和第5位发生II型β - turn。为了验证这一假设，我们合成了5个a因子的类似物，其中位置4和5的残基被替换为：l‐Pro4(I);d‐Pro4(II);l‐Pro4‐d‐Ala5(III);d‐Pro4‐l‐Ala5(IV)；或Nle4 (V)。通过高效液相色谱（HPLC）和薄层色谱（TLC）证实，纯化的类似物均匀性为0.99%，并通过质谱和氨基酸分析对其进行了表征。通过生长抑制实验，发现构象限制性因子类似物I和III的活性几乎是非对视性同源物II和IV的50倍，与野生型因子的活性相同。用等容的nle4取代lys4几乎消除了信息素的活性。因此，促进II型β -转化的残基的结合补偿了lys4侧链对信息素活性有利贡献的损失。这些肽的CD光谱表明，它们在TFE/H2O和DMPC囊泡存在时本质上是无序的。CD峰形态与生物活性无相关性。利用荧光光谱，我们测量了脂质囊泡与这些位置4和5类似物以及与修饰法尼基的三因子类似物的相互作用。结果表明，多肽序列和脂质片段的改变都会影响脂质分裂，信息素分裂脂质的倾向与其生物活性之间不存在相关性。
Previous biochemical investigations on theSaccharomyces cerevisiaea‐factor indicated that this lipopeptide pheromone [YIIKGVFWDPAC(farnesyl)OMe] might adopt a type II β‐turn at positions 4 and 5 of the peptide sequence. To test this hypothesis, we synthesized five analogs ofa‐factor, in which residues at positions 4 and 5 were replaced with:l‐Pro4(I);d‐Pro4(II);l‐Pro4‐d‐Ala5(III);d‐Pro4‐l‐Ala5(IV); or Nle4(V). Analogs were purified to > 99% homogeneity as evidenced by HPLC and TLC and were characterized by mass spectrometry and amino acid analysis. Using a growth arrest assay the conformationally restricteda‐factor analogs I and III were found to be almost 50‐fold more active than the diastereometric homologs II and IV and were equally active to wild‐typea‐factor. Replacement of Lys4with the isosteric Nle4almost abolished the activity of the pheromone. Thus, the incorporation of residues that promote a type II β‐turn compensated for the loss of the favorable contribution of the Lys4side chain to pheromone activity. CD spectra on these peptides suggested that they were essentially disordered in both TFE/H2O and in the presence of DMPC vesicles. There was no correlation between CD peak shape and biological activity. Using fluorescence spectroscopy we measured the interaction of lipid vesicles with these position 4 and 5 analogs as well as with threea‐factor analogs with a modified farnesyl group. The results indicated that modifications of both the peptide sequence and the lipid moiety affect partitioning into lipid, and that no correlation existed between the propensity of a pheromone to partition into the lipid and its biological activity.