The Biofilm Research Laboratory, Institute of Biomedical and Oral Research, The Faculty of Dental Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
Department of Prosthodontics, Hadassah Medical Center, Faculty of Dental Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
Sci Rep. 2022 Sep 27;12(1):16125. doi: 10.1038/s41598-022-20275-8.
Bacillus subtilis biofilms are well known for their complex and highly adaptive morphology. Indeed, their phenotypical diversity and intra-biofilm heterogeneity make this gram-positive bacterium the subject of many scientific papers on the structure of biofilms. The "robustness" of biofilms is a term often used to describe their level of susceptibility to antimicrobial agents and various mechanical and molecular inhibition/eradication methods. In this paper, we use computational analytics to quantify Bacillus subtilis morphological response to proximity to an antimicrobial source, in the form of the antiseptic chlorhexidine. Chlorhexidine droplets, placed in proximity to Bacillus subtilis macrocolonies at different distances result in morphological changes, quantified using Python-based code, which we have made publicly available. Our results quantify peripheral and inner core deformation as well as differences in cellular viability of the two regions. The results reveal that the inner core, which is often characterized by the presence of wrinkled formations in the macrocolony, is more preserved than the periphery. Furthermore, the paper describes a crescent-shaped colony morphology which occurs when the distance from the chlorhexidine source is 0.5 cm, as well as changes observed in the growth substrate of macrocolonies exposed to chlorhexidine.
枯草芽孢杆菌生物膜以其复杂和高度适应的形态而闻名。事实上，它们表型的多样性和生物膜内的异质性使这种革兰氏阳性菌成为许多关于生物膜结构的科学论文的主题。生物膜的“稳健性”是一个常用术语，用于描述其对抗菌剂和各种机械和分子抑制/消除方法的敏感性。在本文中，我们使用计算分析来量化枯草芽孢杆菌形态对靠近抗菌源的反应，抗菌源以防腐剂洗必泰的形式存在。将洗必泰液滴放置在枯草芽孢杆菌大菌落的不同距离处，会导致形态发生变化，我们使用基于 Python 的代码对其进行了量化，并将其公开。我们的结果量化了两个区域的外围和核心变形以及细胞活力的差异。结果表明，核心区域（通常以大菌落中存在褶皱结构为特征）比外围区域保存得更好。此外，本文还描述了当与洗必泰源的距离为 0.5 厘米时出现的新月形菌落形态，以及暴露于洗必泰的大菌落生长基质中观察到的变化。
