联合单颗粒质谱与Score-CAM算法判定分析萎缩芽孢杆菌营养细胞和芽孢  

Combined Single Particle Mass Spectrometry and Score-CAM Algorithm for Differentiation and Analysis of Vegetative Cells and Spores of Bacillus atrophaeus

作　　者：陈红 张宁 杜耀华 詹晓波 程智 CHEN Hong;ZHANG Ning;DU Yao-hua;ZHAN Xiao-bo;CHENG Zhi(Systems Engineering Institute,Academy of Military Sciences,Tianjin 300161,China)

机构地区：[1]军事科学院系统工程研究院,天津300161

出　　处：《质谱学报》2025年第2期175-186,I0002,共13页Journal of Chinese Mass Spectrometry Society

摘　　要：萎缩芽孢杆菌(ATCC-9372)是一株重要的芽孢杆菌属菌株,利用单颗粒质谱技术区分萎缩芽孢杆菌营养细胞和芽孢的独特生化标志物,对理解其生物学特性和代谢途径具有重要意义。近年来,国内外单颗粒质谱技术取得了很大进展,但是,随着质谱数据处理算法的不断丰富,还未见联合先进的深度学习算法与单颗粒质谱技术区分不同状态萎缩芽孢杆菌的报道。本研究利用深度学习算法和分类模型可视化方法区分萎缩芽孢杆菌的营养细胞和芽孢,并从粒径和质谱离子特征角度进行分析。通过对比粒径发现,营养细胞的粒径大于芽孢,不同采样时间点的营养细胞的粒径大小基本一致。另外,采用相同的方法建立用于训练及测试分类模型的数据集和用于评价模型分类稳定性的验证集,发现模型在测试集和验证集上的识别准确率均在99%以上;对Score-CAM结果中得分高的特征离子进行成分溯源分析,通过箱型图展现了这些特征离子信号强度的分布差异。本研究从生化角度对不同状态下的萎缩芽孢杆菌进行深入分析,可为质谱数据的处理分析提供思路和方法。Bacillus atrophaeus(ATCC-9372)is an important strain of the Bacillus genus.The use of single particle mass spectrometry to distinguish unique biochemical markers of vegetative cells and spores of Bacillus atrophicus is important for understanding their biological properties.The main objective of this study is to distinguish vegetative cells and spores of Bacillus atrophaeus by analyzing the diameter and characteristic mass spectrometry ions of Bacillus atrophaeus by combined using of deep learning algorithms and classification model visualization methods.Firstly,the samples were prepared by collecting and centrifuging Bacillus atrophaeus that has been cultured for a certain period,and the spore samples of Bacillus atrophaeus were diluted.Then,single particle mass spectrometry was used to collect particle size and mass spectrometry data for the above two samples and to construct mass spectrometry datasets for the two objects.Following this,the particle sizes of the two samples were compared,and the datasets were divided.Based on the Matlab platform,a Convolutional Neural Network(CNN)classification model was trained to analyze the experimental results.Lastly,the typical ion characteristics of each were analyzed according to the average mass spectra,and the CNN classification process was visually analyzed using the Score-CAM algorithm.The differential ion characteristics between the vegetative cells and spores of Bacillus atrophaeus were extracted and analyzed.It was found that the particle size of vegetative cells is larger than that of spores,and the particle size of vegetative cells is essentially consistent at different sampling times.The CNN classification model achieves an accuracy of over 99%on both the test set and the validation set,indicating that the CNN model can fully learn and analyze the mass spectrometry characteristics.Their respective typical ion characteristics were analyzed by comparing the average mass spectra,which led to the introduction of their compositional differences,but not all typical i

关 键 词：单颗粒质谱 萎缩芽孢杆菌 营养细胞 芽孢 1D-CNN Score-CAM 

分 类 号：O657.63[理学—分析化学]