The presence of Cysteine 26 in Wheat germ (Triticum aestivum) calmodulin (CaM) makes it unique vis-a-vis mammalian calmodulin. In contrast to mammalian CaMs, which lack cysteine, this preparation is ideal for applications requiring both calmodulin activation and residue specific tagging. The single SH moiety at Cys26 can be labeled using a variety of sulfhydryl (SH) reactive protein-modification reagents such as fluorescent maleimide derivatives. The presence of a single C-terminal tyrosine residue at the138 position (Tyr138) as against two tyrosines in mammalian calmodulin makes Tyr138 suitable as a mono-specific tag. Using Cys26 and Tyr138 allows wheat germ CaM to be independently derivatized at both N- and C-terminal regions within the molecule for structural, proteomic biomarker discovery and protein-protein interaction studies. Wheat germ CaM also has no tryptophan resulting in a distinctive absorbance spectrum when compared to mammalian CaM sequences. Calmodulin (CaM) is a ubiquitous, calcium-binding protein that binds and regulates a multitude of protein targets, many of which are involved in the Alzheimer"s and the Parkinson"s pathways
1,4. CaM has a molecular weight of about 17kDa, containing 148 amino acids, and pI of 3.9. CaM is characterized by two domains, connected by an alpha-helix chain. Each domain has the capacity to bind two calcium ions. Binding Ca
2+ ions causes a conformational change in CaM, making it available for interaction with target proteins. Hence, CaM functions as an intracellular calcium ion bridge to mediate cellular reactions and responds appropriately to calcium ion concentration. In Alzheimer"s disease (AD), irregular calcium homeostasis seems to trigger CaM and its binding proteins, to enhance plaque formation and neurofibrillary degeneration, which results in cell death
1. The increased cytosolic levels of Ca
2+ in AD neurons promotes CaM binding and regulation of available Ca
2+/CaM-dependent CaM-binding proteins, associated with amyloid beta (Ab) formation. In addition, the increased level of Ca
2+ triggers Calmodulin to activate calcium/CaM-dependent kinase II and precede neurofibrillary tangle formation
2,4. In Parkinson"s disease (PD), Calmodulin has been found to interact, in a calcium dependent manner, with Alpha-Synuclein, which is associated with the progression of PD. CaM was identified as one of the synuclein-interacting proteins that regulate synuclein conformation
3.
rPeptide是一家生物化学公司,坐落于美国乔治亚州,与雅典毗邻。该公司研发试剂是市场领跑者。主要产品涉及领域为老年性痴呆症与帕金森综合症研究使用的重组蛋白,重组多肽,抗体以及试剂等等,并成为了该领域的领导者。同时,该公司提供一系列外包服务,从分子生物学,蛋白表达与蛋白纯化到13C与15N统一标记蛋白与多肽。rPeptide技术平台可解决可溶性多肽/蛋白(例如:β-淀粉样蛋白、廋蛋白、前胰岛素)在大肠杆菌中表达等历史性难题。
1、Beta-AmyloidPeptides β-淀粉样多肽系列产品
2、 Proteins 蛋白系列产品
3、 Labeledpeptides&proteins 标记多肽与标记蛋白系列产品
4、MonoclonalAntibodies 单克隆抗体系列产品
5、PolyclonalAntibodies 多克隆抗体
6、Bydisease 人类疾病相关产品
7、Contractservices 外包服务
7.1 RecombinantExpressionofPeptidesandProteins 多肽与蛋白重组表达
7.2 UniformLabelingofPeptidesandProteins 多肽与蛋白进行标记
7.3 SyntheticPeptideSynthesis 多肽合成