Discrete Forms of Amylose Are Synthesized by Isoforms of GBSSI in Pea Online version contains Web-only data. Article, publication date, and citation information can be found at www.plantcell.org/cgi/doi/10.1105/tpc.002907.
Discrete Forms of Amylose Are Synthesized by Isoforms of GBSSI in Pea Online version contains Web-only data. Article, publication date, and citation information can be found at www.plantcell.org/cgi/doi/10.1105/tpc.002907.
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豌豆在线版本中的 GBSSI 异构体合成了离散形式的直链淀粉，仅包含 Web 数据。
DOI：
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
Cathie Martin
中科院分区：
文献类型：
--
作者：
A. Edwards;J. Vincken;L. Suurs;R. Visser;S. Zeeman;Alison M. Smith;Cathie Martin
与豌豆叶淀粉相比，豌豆胚淀粉中的直链淀粉具有不同的分子量。在豌豆胚中，颗粒结合淀粉合成酶蛋白（GBSSIa）是合成大部分直链淀粉所必需的。然而，这种蛋白质在豌豆叶片直链淀粉的合成中似乎是微不足道的。编码GBSSI的第二种同种型GBSSIb的cDNA克隆已从豌豆叶中分离。比较GBSSIa和GBSSIb的活性表明它们具有不同的性质。这些差异已经通过马铃薯无直链淀粉突变体中GBSSIa和GBSSIb的表达得到证实。GBSSIa和GBSSIb形成分子量不同的直链淀粉的不同形式。这些产品特异性的差异，再加上GBSSIa和GBSSIb最活跃的组织的差异，解释了豌豆不同组织中发现的不同形式的直链淀粉。由GBSSIa形成的较短形式的直链淀粉比由GBSSIb形成的直链淀粉对淀粉糊的老化的敏感性更低。GBSSIa的产品特异性可以为食品和非食品用途的淀粉提供有益的属性。
Amyloses with distinct molecular masses are found in the starch of pea embryos compared with the starch of pea leaves. In pea embryos, a granule-bound starch synthase protein (GBSSIa) is required for the synthesis of a significant portion of the amylose. However, this protein seems to be insignificant in the synthesis of amylose in pea leaves. cDNA clones encoding a second isoform of GBSSI, GBSSIb, have been isolated from pea leaves. Comparison of GBSSIa and GBSSIb activities shows them to have distinct properties. These differences have been confirmed by the expression of GBSSIa and GBSSIb in the amylose-free mutant of potato. GBSSIa and GBSSIb make distinct forms of amylose that differ in their molecular mass. These differences in product specificity, coupled with differences in the tissues in which GBSSIa and GBSSIb are most active, explain the distinct forms of amylose found in different tissues of pea. The shorter form of amylose formed by GBSSIa confers less susceptibility to the retrogradation of starch pastes than the amylose formed by GBSSIb. The product specificity of GBSSIa could provide beneficial attributes to starches for food and nonfood uses.
DOI：
10.1073/pnas.85.23.8998
发表时间：
1988-12-01
影响因子：
11.1
作者：
FROHMAN, MA;DUSH, MK;MARTIN, GR
通讯作者：
MARTIN, GR