Identification and sub-typing of food-born bacteria from animal feed ingredients, animal feed & pet foods samples using Matrix-Assisted Laser Desorption & Ionization Time-of-Flight Mass Spectrometry.

FDA CVM VET-LRN计划(U18)拨款建议书 FOA#PA-13-244，CFDA 93,103 项目摘要/摘要 该项目将使用基质辅助激光解吸电离飞行时间质量 用于鉴定人类食源性病原体的光谱(MALDI-TOF MS)，包括 沙门氏菌、大肠杆菌、弯曲杆菌、单核细胞增生性李斯特菌、产气荚膜梭菌、 动物饲料配料、宠物食品和动物饲料中的金黄色葡萄球菌。第一年 该项目的重点将是利用MALDI技术对沙门氏菌进行鉴定和分型。 TOF MS将在以下四个方面对其他食源性致病菌使用相同的方法 好几年了。宠物食品/动物饲料中的沙门氏菌污染已导致人类 沙门氏菌病。然而，动物饲料成分、动物饲料和宠物食品的污染 食物还没有被系统地研究过。常规培养是“黄金标准”的方法 用于隔离和鉴定。这种方法劳动强度大、成本高、耗时长， 在被污染的动物分发之前没有提供及时的信息 食物基质。因此，快速可靠的鉴定和分型的替代方法 迫切需要沙门氏菌来改善动物饲料供应的安全性和完整性， 这反过来将限制人类感染。在本应用程序中，我们建议开发方法 MALDI-TOF MS用于沙门氏菌的快速、特异鉴定和分型 在动物饲料基质的初步培养皿上生长。微生物鉴定使用 这项技术是基于对直接从细胞或 使用模式识别算法对参考光谱进行细胞提取。这项技术是 目前以商业平台的形式提供，并进行了大量的研究 已经产生了证明其对沙门氏菌的鉴定和分型的有效性。 我们已成功地将这项技术用于粪便和粪便中沙门氏菌的鉴定 动物组织样本。然而，对MALDI-TOF的使用缺乏了解 MS用于鉴定宠物食品和动物饲料基质中的细菌分离物。建议数 研究将通过以下三个具体目标解决这些问题： 具体目标1：各种动物食源性细菌分离株的鉴定和分型 使用新型文库的MALDI-TOF MS食品基质。 具体目标2：直接从生长的菌落中鉴定食源性细菌并进行分型 在动物饲料和食物基质的各种培养介质上。 具体目标3：将这一新方法移植和培训给其他兽医-LIRN 实验室。 该项目的成功完成将扩大这项技术目前的应用范围 粪便和动物组织样本到动物饲料基质中，以提高安全和完整性 美国动物饲料供应。此外，多个实验室对此进行了协作验证 方法论将提高Vet-LIRN实验室的能力和能力，以服务于云服务器 在应对动物性食品污染事件时需要快速周转时间。

FDA CVM VET-LRN PROGRAM (U18) GRANT PROPOSAL FOR FOA # PA-13-244, CFDA 93, 103 Project Summary/Abstract This project will use Matrix-Assisted Laser Desorption Ionization Time-of-Flight mass spectrometry (MALDI-TOF MS) for identification of human foodborne pathogens, including Salmonella, E. coli, Campylobacter species, Listeria monocytogenes, Clostridium perfringens, and Staphylococcus aureus in animal feed ingredients, pet foods and animal feed. The first year of the project will focus on identification and subtyping of Salmonella bacteria using MALDI- TOF MS. The same approach will be used for other foodborne pathogens in the following four years. Salmonella contamination of pet foods/animal feeds has resulted in outbreaks of human Salmonellosis. However, contamination of animal feed ingredients, animal feed, and pet treats and foods have not been systematically studied. Routine culture is the "gold standard" method for isolation and identification. This method is labor intensive, expensive, and time consuming, which does not provide timely information before the distribution of the contaminated animal food matrices. Therefore, alternative methods for rapid and reliable identification and subtyping of Salmonella bacteria are urgently needed to improve safety and integrity of animal feed supply, which in turn will limit human infections. In this application we propose to develop methods using MALDI-TOF MS for rapid and specific identification and typing of Salmonella bacteria grown on preliminary culture plates from animal feed matrices. Microbial identification using this technology is based on the comparison of spectral patterns obtained directly from cells or cell extracts against reference spectra using a pattern recognition algorithm. This technology is currently available in the form of commercial platforms, and a considerable amount of studies have been generated demonstrating its utility for identification and typing of Salmonella bacteria. We have successfully used this technology for identification of Salmonella bacteria in fecal and animal tissue samples. There is, however, a lack of knowledge regarding the use of MALDI-TOF MS for identification of bacterial isolates from pet food and animal feed matrices. The proposed study will address these issues by the following three specific aims: Specific aim 1: Identification and subtyping of foodborne bacterial isolates from various animal food matrices using MALDI-TOF MS using a novel library. Specific aim 2: Identification and subtyping of foodborne bacteria directly from colonies grown on various culture media from animal feed and food matrices. Specific aim 3: Transferring and training of this new methodology to other Vet-LIRN laboratories. Successful completion of this project will expand the current application of this technology from fecal and animal tissue samples to animal feed matrices to improve the safety and integrity of the US animal feed supply. In addition, the multi-laboratory collaboration validation of this methodology will increase Vet-LIRN laboratory capability and capacity in order to serve CVM's need for rapid turnaround times when responding to animal food contamination events.