Bracchi-Ricard V, Nguyen K T, Zhou Y, Rajagopalan P T, Chakrabarti D, Pei D
Department of Molecular Biology & Microbiology, University of Central Florida, Orlando, FL 32816, USA.
Arch Biochem Biophys. 2001 Dec 15;396(2):162-70. doi: 10.1006/abbi.2001.2631.
Ribosomal protein synthesis in eubacteria and eukaryotic organelles initiates with an N-formylmethionyl-tRNA(i), resulting in N-terminal formylation of all nascent polypeptides. Peptide deformylase (PDF) catalyzes the subsequent removal of the N-terminal formyl group from the majority of bacterial proteins. Until recently, PDF has been thought as an enzyme unique to the bacterial kingdom. Searches of the genomic DNA databases identified several genes that encode proteins of high sequence homology to bacterial PDF from eukaryotic organisms. The cDNA encoding Plasmodium falciparum PDF (PfPDF) has been cloned and overexpressed in Escherichia coli. The recombinant protein is catalytically active in deformylating N-formylated peptides, shares many of the properties of bacterial PDF, and is inhibited by specific PDF inhibitors. Western blot analysis indicated expression of mature PfPDF in trophozoite, schizont, and segmenter stages of intraerythrocytic development. These results provide strong evidence that a functional PDF is present in P. falciparum. In addition, PDF inhibitors inhibited the growth of P. falciparum in the intraerythrocytic culture.
真细菌和真核细胞器中的核糖体蛋白质合成起始于N-甲酰甲硫氨酰-tRNA(i)，导致所有新生多肽的N端甲酰化。肽脱甲酰基酶（PDF）催化随后从大多数细菌蛋白质中去除N端甲酰基。直到最近，PDF一直被认为是细菌界特有的一种酶。对基因组DNA数据库的搜索发现了几个基因，这些基因编码与真核生物细菌PDF具有高度序列同源性的蛋白质。编码恶性疟原虫PDF（PfPDF）的cDNA已被克隆并在大肠杆菌中过表达。重组蛋白在使N-甲酰化肽脱甲酰基方面具有催化活性，具有许多细菌PDF的特性，并被特定的PDF抑制剂抑制。蛋白质印迹分析表明成熟的PfPDF在红细胞内发育的滋养体、裂殖体和裂殖子阶段表达。这些结果提供了强有力的证据，证明恶性疟原虫中存在一种功能性PDF。此外，PDF抑制剂抑制了红细胞内培养的恶性疟原虫的生长。
