Biochemical and genetic mechanisms used by plant growth-promoting bacteria

“植物生长促进细菌”一词描述的是与植物(通常是根)有益结合的土壤细菌。这些细菌使用各种机制来促进植物的生长。然而，为了使植物生长促进细菌在农业、园艺和环境清理中的使用更加有效、可预测和可重复性，有必要首先了解支配这些生物和植物之间关系的基本遗传和生化机制。在这方面，植物生长促进细菌使用的主要机制之一涉及1-氨基环丙烷-1-羧酸(ACC)脱氨酶，该酶裂解化合物ACC，该化合物是所有高等植物中植物激素乙烯的直接前体。含有ACC脱氨酶的植物生长促进细菌菌株为多种不同的植物物种提供了显著的保护，使其免受各种环境胁迫的伤害，这些环境胁迫包括植物病原体、洪水、重金属、干旱、极端温度、有机环境污染物的存在和高盐。在这里提出的工作中：将详细阐述植物生长促进细菌和植物如何影响彼此的基因表达的细节；将调查具有ACC脱氨酶功能的共生细菌的一些细节；并努力了解仅与植物根结合的植物生长促进细菌在促进植物生长方面与那些定居在植物内部的植物生长促进细菌有何不同。

The term "plant growth-promoting bacteria" describes soil bacteria that are involved in a beneficial association with plants (often with the roots). These bacteria use a variety of mechanisms to facilitate plant growth. However, in order to make the use of plant growth-promoting bacteria in agriculture, horticulture and environmental cleanup, more efficacious, predictable and reproducible, it is necessary to first understand the fundamental genetic and biochemical mechanisms that govern the relationship between these organisms and plants. In this regard, one of the major mechanisms used by plant growth-promoting bacteria involves the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase which cleaves the compound ACC, the immediate precursor of the phytohormone ethylene in all higher plants. Plant growth-promoting bacterial strains that contain ACC deaminase provide a wide range of different plant species with a significant level of protection from the damage caused by various environmental stresses including phytopathogens, flooding, heavy metals, drought, temperature extremes, the presence of organic environmental contaminants, and high salt. In the work that is proposed here: the details of how plant growth-promoting bacteria and plants impact one another's gene expression will be elaborated; some of the details of how symbiotic bacteria with ACC deaminase function will be investigated; and efforts will be made to understand how plant growth-promoting bacteria that bind only to a plant's roots differ from those that colonize the interior of the plant in their promotion of plant growth.