Putative mitosomal proteins classified by predicted function: Iron-sulfur cluster assembly, chaperones, redox mechanism and protein translocation and processing.

Mascot score, Mascot total ion score for the identified protein. Coverage, number of unique peptides per identified protein. MiD, mitosomal distribution. Proteins are marked “Y” if their distributions in fractions #3 and #4 of the Optiprep gradient (measured by the iTRAQ ratio) were within the range between Cpn10 and IscU and the window that extended in both directions by half of the distance between these markers. Proteins with ratios outside of this range are indicated with “N”. TargetP and PsortII were used to predict the subcellular location of Giardia proteins. S, secretory; N, non-secretory; M, mitochondrial; O, other. Exp. ver., experimental verification of protein localization using the pONDRA expression vector. The recombinant tagged proteins were localized by fluorescence microscopy. M, mitosome; ER, endoplasmic reticulum; O, other; ? inconclusive. MEMSAT3 and TMHMM were used to predict transmembrane domains. SGP, predicted soluble proteins are marked with number sign (#). Asterisk (*) is used where no data were available. (**) transformed Giardia did not express the recombinant tagged protein.

Mascot 评分（Mascot score）：指用于鉴定蛋白的Mascot总离子评分（Mascot total ion score）。覆盖率（Coverage）：单个鉴定蛋白所对应的独特肽段数量。MiD：线粒体体分布（mitosomal distribution，MiD）。若蛋白在Optiprep密度梯度（Optiprep gradient）的第3、4组分中的分布（通过iTRAQ比值（iTRAQ ratio）测定）处于Cpn10与IscU之间，且向两侧延伸至这两个标记物间距一半的区间内，则标记为“Y”；分布超出该范围的蛋白则标记为“N”。采用TargetP与PsortII工具预测贾第虫（Giardia）蛋白的亚细胞定位：S代表分泌型（secretory）、N代表非分泌型（non-secretory）、M代表线粒体相关型（mitochondrial）、O代表其他类型（other）。Exp. ver.：采用pONDRA表达载体（pONDRA expression vector）开展蛋白定位的实验验证。通过荧光显微镜（fluorescence microscopy）对重组标签蛋白进行定位观察：M代表线粒体体（mitosome）、ER代表内质网（endoplasmic reticulum，ER）、O代表其他类型，？表示结果无法确定（inconclusive）。采用MEMSAT3与TMHMM工具预测跨膜结构域（transmembrane domains）。SGP：预测得到的可溶性蛋白以井号（#）标注。星号（*）用于标注无可用数据的条目。(**) 表示转化的贾第虫未成功表达重组标签蛋白。