Phycobiliproteins are colored, active molecules with potential use in different industries. They are the union of proteins and bilins (Chromophores). The primary source of phycobiliproteins is algae; however, the traditional algae culture has production restrictions. The production in bacterial models can be a more efficient alternative to produce these molecules. However, the lack of knowledge in some steps of the phycobiliprotein metabolic pathway limits this alternative. Porphyridium cruentum is a single cell red alga with a high phycobiliprotein content. Its protein sequences were the basis for phycobilin production in this study. In this study, we cloned and characterized enzymes presumably involved in the chromophore production of P. cruentum. Using sequences obtained from its transcriptome, we characterized two cDNA sequences predicted to code respectively for a ferredoxin-dependent bilin reductase and a bilin lyase-isomerase. We expressed these enzymes in Escherichia coli to obtain in vivo evidence of their enzymatic activity on the substrate biliverdin IXα. Lastly, we analyzed them using thin-layer chromatography, spectrophotometry, and fluorescence spectroscopy. These experiments provided evidence of bilin modification. The expressed bilin lyase-isomerase did not show significant activity over the biliverdin molecule. On the contrary, the expressed ferredoxin-dependent bilin reductase showed activity over the biliverdin.

藻胆蛋白是有色活性分子，在不同行业具有潜在用途。它们是蛋白质和胆素（生色团）的结合。藻胆蛋白的主要来源是藻类；然而，传统的藻类养殖有生产限制。在细菌模型中生产可以是生产这些分子的更有效的替代方法。然而，在藻胆蛋白代谢途径的某些步骤中缺乏知识限制了这种选择。Porphyridium cruentum是一种具有高藻胆蛋白含量的单细胞红藻。其蛋白质序列是本研究中藻胆素生产的基础。在这项研究中，我们克隆并表征了可能参与P. cruentum生色团产生的酶. 使用从其转录组中获得的序列，我们表征了预测分别编码铁氧还蛋白依赖性胆碱还原酶和胆碱裂解酶异构酶的两个 cDNA 序列。我们在大肠杆菌中表达了这些酶，以获得它们对底物胆绿素 IXα 的酶活性的体内证据。最后，我们使用薄层色谱法、分光光度法和荧光光谱法对它们进行了分析。这些实验提供了胆蛋白修饰的证据。表达的胆素裂解酶异构酶对胆绿素分子没有表现出显着的活性。相反，表达的铁氧还蛋白依赖性胆色素还原酶显示出超过胆绿素的活性。