Nitzschia is one of the largest genera of diatoms found in a range of aquatic environments, from freshwater to seawater. This genus contains evolutionarily and ecologically unique species, such as those that have lost photosynthetic capacity or those that live symbiotically in dinoflagellates. Several Nitzschia species have been used as indicators of water pollution. Recently, Nitzschia species have attracted considerable attention in the field of biotechnology. In this study, a transformation method for the marine pennate diatom Nitzschia sp. strain NIES-4635, isolated from the coastal Seto Inland Sea, was established. Plasmids containing the promoter/terminator of the fucoxanthin chlorophyll a/c binding protein gene (fcp, or Lhcf) derived from Nitzschia palea were constructed and introduced into cells by multi-pulse electroporation, resulting in 500 μg/mL nourseothricin-resistant transformants with transformation frequencies of up to 365 colonies per 10⁸ cells. In addition, when transformation was performed using a new plasmid containing a promoter derived from a diatom-infecting virus upstream of the green fluorescent protein gene (gfp), 44% of the nourseothricin-resistant clones exhibited GFP fluorescence. The integration of the genes introduced into the genomes of the transformants was confirmed by Southern blotting. The Nitzschia transformation method established in this study will enable the transformation this species, thus allowing the functional analysis of genes from the genus Nitzschia, which are important species for environmental and biotechnological development.

菱形藻是在从淡水到海水的一系列水生环境中发现的最大的硅藻属之一。该属包含进化和生态上独特的物种，例如那些失去光合作用能力的物种或与甲藻共生的物种。几种菱形藻已被用作水污染的指标。近年来，菱形藻在生物技术领域引起了广泛关注。在本研究中，海洋羽状硅藻菱形藻的转化方法。菌株 NIES-4635 是从濑户内海沿岸分离出来的。构建含有源自古菱形藻的岩藻黄质叶绿素a/c结合蛋白基因（fcp或Lhcf ）启动子/终止子的质粒，并通过多脉冲电穿孔导入细胞，产生 500 μg/mL 诺尔丝菌素抗性转化子。每 10 ^{8 个}细胞最多有 365 个集落的频率。此外，当使用绿色荧光蛋白基因（ gfp ）上游含有来自硅藻感染病毒的启动子的新质粒进行转化时，44%的诺尔丝菌素抗性克隆表现出GFP荧光。通过Southern印迹证实了引入转化体基因组中的基因的整合。本研究中建立的菱形藻转化方法将能够对该物种进行转化，从而可以对菱形藻属的基因进行功能分析，菱形藻属是环境和生物技术发展的重要物种。