Heterologous expression of human C‐reactive protein in the green alga Chlamydomonas reinhardtii

C-reactive protein (CRP) participates in human inflammatory responses and is an important indicator in clinical diagnoses. At present, the use of monoclonal antibodies to detect CRP in the human body is high, but they are unstable and expensive. Understanding the CRP expression pathway is of great significance for developing CRP tests and reagents. Chlamydomonas reinhardtii is a model organism that has great potential as a foreign protein expression system. This study is the first attempt to express human CRP in C. reinhardtii. We selected the endogenous constitutive Rbcs2 promoter and terminator and used ble as a selective gene to construct a C. reinhardtii nuclear expression vector containing CRP. After transformation using the glass bead method, six positive transformants were obtained. At the molecular level, full-length CRP was transformed into the genome of C. reinhardtii CC400 cells, and human CRP was expressed. This study provides new insights into obtaining active CRP. Practical applications Based on the nuclear transformation system of C. reinhardtii, it can construct an exogenous protein expression system that produces a variety of high value-added products and can be used to produce a variety of high value-added proteins, functional drugs, and industrial raw materials. It has broad market prospects and huge application prospects.