Lactic acid bacteria (LAB) is mainly used in food fermentation. In addition, LAB fermentation technology has been studied in the development of industrial food additives, nutrients, or enzymes used in food processing. In the field of red biotechnology, LAB is approved and is generally recognized as a safe organism and is considered safe for biotherapeutic treatments. Recent clinical trials have demonstrated the medicinal value of therapeutic recombinant LAB and the suitability of innate mechanisms of secretion and anchoring for therapeutic applications such as antibody or vaccine production. However, the gram‐positive phenotypic trait of LAB creates challenges for genetic modifications when compared to other conventional workhorse bacteria, resulting in exclusive developments of genetic tools for engineering LAB. In this review, several distinct approaches in gene expression for engineering LAB are discussed.

中文翻译：

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开发重组乳酸菌的工程工具。

乳酸菌（LAB）主要用于食品发酵中。此外，在食品加工中使用的工业食品添加剂，营养物质或酶的开发中，还对LAB发酵技术进行了研究。在红色生物技术领域，LAB被批准并被普遍认为是安全的有机体，并被认为对于生物治疗而言是安全的。最近的临床试验证明了治疗性重组LAB的药用价值以及固有的分泌和锚定机制对于治疗性应用（例如抗体或疫苗生产）的适用性。然而，与其他常规主力细菌相比，乳酸菌的革兰氏阳性表型性状对遗传修饰提出了挑战，导致了专门用于遗传工程乳酸菌的遗传工具的发展。在这篇评论中