Cui Lijuan, Xu Haiyan, Zhu Zhaoxia, Gao Xiang
School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, P. R. China.
School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan 430079, P. R. China
Biol Open. 2017 Sep 15;6(9):1329-1335. doi: 10.1242/bio.026955.
The terrestrial cyanobacterium , which contributes to carbon and nitrogen supplies in arid and semi-arid regions, adopts a filamentous colony form. Owing to its herbal and dietary values, this species has been overexploited. Largely due to the lack of understanding on its morphogenesis, artificial cultivation has not been achieved. Additionally, it may serve as a useful model for recognizing the morphological adaptation of colonial cyanobacteria in terrestrial niches. However, it shows very slow growth in native habitats and is easily disintegrated under laboratory conditions. Thus, a novel experimental system is necessary to explore its morphogenetic mechanism. Liquid-cultured has been well developed for exopolysaccharide (EPS) production, in which microscopic colonies (micro-colonies) are generally formed. In this study, we sought to gain some insight into the morphogenesis of by examining the effects of two external factors, the EPS and environmental stress-related growth rate, on the morphological shaping of micro-colonies. Our findings indicate that the EPS matrix could act as a basal barrier, leading to the bending of trichomes during their elongation, while very slow growth is conducive to their straight elongation. These findings will guide future cultivation and application of this cyanobacterium for ecological improvement.
这种陆生蓝细菌以丝状群体形式存在，对干旱和半干旱地区的碳氮供应有贡献。由于其药用和食用价值，该物种已被过度开发。很大程度上由于对其形态发生缺乏了解，尚未实现人工栽培。此外，它可能是认识陆生生态位中群体蓝细菌形态适应的有用模型。然而，它在原生栖息地生长非常缓慢，在实验室条件下容易解体。因此，需要一个新的实验系统来探索其形态发生机制。液体培养已被很好地用于胞外多糖（EPS）生产，在此过程中通常会形成微观菌落（微菌落）。在本研究中，我们试图通过研究两个外部因素，即EPS和与环境胁迫相关的生长速率，对微菌落形态塑造的影响，来深入了解该蓝细菌的形态发生。我们的研究结果表明，EPS基质可作为一个基础屏障，导致藻丝在伸长过程中弯曲，而非常缓慢的生长有利于其笔直伸长。这些发现将指导该蓝细菌未来用于生态改善的栽培和应用。
