Laboratory of Protein Chemistry and Biochemistry, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasilia, Brazil.
Laboratory of Plant Biochemistry, Department of Botany, Institute of Biology, University of Brasilia, Brasilia, Brazil.
Sci Rep. 2023 Feb 14;13(1):2602. doi: 10.1038/s41598-023-29857-6.
Corynebacterium glutamicum is a bacterium widely employed in the industrial production of amino acids as well as a broad range of other biotechnological products. The present study describes the characterization of C. glutamicum proteoforms, and their post-translational modifications (PTMs) employing top-down proteomics. Despite previous evidence of PTMs having roles in the regulation of C. glutamicum metabolism, this is the first top-down proteome analysis of this organism. We identified 1125 proteoforms from 273 proteins, with 60% of proteins presenting at least one mass shift, suggesting the presence of PTMs, including several acetylated, oxidized and formylated proteoforms. Furthermore, proteins relevant to amino acid production, protein secretion, and oxidative stress were identified with mass shifts suggesting the presence of uncharacterized PTMs and proteoforms that may affect biotechnologically relevant processes in this industrial workhorse. For instance, the membrane proteins mepB and SecG were identified as a cleaved and a formylated proteoform, respectively. While in the central metabolism, OdhI was identified as two proteoforms with potential biological relevance: a cleaved proteoform and a proteoform with PTMs corresponding to a 70 Da mass shift.
谷氨酸棒杆菌是一种广泛应用于工业生产氨基酸和其他多种生物技术产品的细菌。本研究采用自上而下的蛋白质组学方法描述了谷氨酸棒杆菌蛋白异构体及其翻译后修饰（PTM）的特征。尽管先前有证据表明 PTM 在谷氨酸棒杆菌代谢的调控中起作用，但这是对该生物体进行的首次自上而下的蛋白质组分析。我们从 273 种蛋白质中鉴定出了 1125 种蛋白异构体，其中 60%的蛋白质至少存在一个质量转移，表明存在 PTM，包括几种乙酰化、氧化和甲酰化的蛋白异构体。此外，还鉴定到了与氨基酸生产、蛋白质分泌和氧化应激相关的蛋白质，其质量转移表明存在未被表征的 PTM 和蛋白异构体，可能会影响该工业用菌中与生物技术相关的过程。例如，膜蛋白 mepB 和 SecG 分别被鉴定为一个裂解和一个甲酰化的蛋白异构体。在中心代谢中，OdhI 被鉴定为两种具有潜在生物学意义的蛋白异构体：一种裂解的蛋白异构体和一种具有对应于 70 Da 质量转移的 PTM 的蛋白异构体。
