Abstract: 【Objective】To compare and analyze the community structure，diversity and potential gene function differences of psychrophilic bacteria in camel milk from different regions and different seasons in Xinjiang，China.【Methods】20 samples of camel milk were collected during spring and summer in Urumqi and Hami，Xinjiang. Culturable psychrophilic bacteria were isolated and identified using traditional cultivation techniques. Subsequently，single molecule real time sequencing（SMRT）was employed to analyze the community composition and relative abundance of taxa of psychrophilic bacteria in camel milk from different regions and seasons. The study further elucidated the differences in community composition of psychrophilic bacteria in camel milk sourced from different regions and seasons by analyzing taxon groups，α diversity，and β diversity.【Results】Through 16S rDNA sequence identification，a total of 214 isolates of psychrophilic bacteria were obtained，spanning 23 genera and 40 species. Acinetobacter emerged as the most frequently isolated psychrophilic bacterium. SMRT sequencing analysis revealed Epilithonimonas as the most abundant psychrophilic bacterium overall. Through intergroup difference analysis，there were significant seasonal differences of psychrophilicbacterial communities in camel milk，with 10 taxa showing significant abundance differences across regions and 25 taxa exhibiting significant abundance variations across seasons. Non-parametric analysisof psychrophilic bacteria prediction function showed that the complex psychrophilicbacterial interdependence with prediction function mainly occurred in metabolic pathways（82.04%），which also revealed that there are clear regional and seasonal differences in level 3 metabolic pathways such as amino acids，carbohydrates，and vitamins in camel milk.【Conclusion】Given the rich diversity of psychrotrophic bacteria species and composition in Xinjiang camel milk. targeted prevention and control measures must be implemented for farms in different regions and different seasons.

Key words: camel milk; diversity of psychrophilic bacteria; community structure of psychrophilic bacteria; SMRT sequencing; function prediction

摘要： 【目的】对比分析新疆不同地区和不同季节驼乳中嗜冷菌的群落结构、多样性及其潜在基因功能差异，为今后驼乳及其制品的生产和食用提供安全保障。【方法】采集新疆乌鲁木齐市达坂城区、哈密市伊州区不同季节驼乳样品20份，通过传统培养法对驼乳中可培养嗜冷菌进行分离鉴定，基于传统培养获得的鉴定结果，利用单分子实时测序法（Single molecule real time sequencing，SMRT）深入分析嗜冷菌整体菌群结构及各种嗜冷菌在不同地区和不同季节驼乳中的相对丰度，进一步通过分类单元组间差异分析、α多样性以及β多样性揭示不同来源驼乳中嗜冷菌群落组成的差异。【结果】通过16S rDNA序列鉴定，共分离出214株嗜冷菌分离株，分为23个属和40个种，其中不动杆菌属（Acinetobacter）为分离频率最高的嗜冷菌属。SMRT测序结果显示，Epilithonimonas为相对丰度最高的嗜冷菌属。通过组间差异分析，嗜冷菌群落具有明显的季节性差异，其中10个嗜冷菌分类单元在不同地区分组丰度差异显著，25个嗜冷菌分类单元在不同季节分组丰度差异显著。非参数检验的功能预测揭示了嗜冷菌与代谢途径具有很强的相互依赖性（82.04%），驼乳中氨基酸、碳水化合物和维生素等代谢途径存在明显的地区和季节差异。【结论】新疆驼乳中嗜冷菌种类和组成结构丰富多样，因此需要针对不同地区和不同季节的养殖场采取不同的嗜冷菌防控措施。

关键词: 驼乳, 嗜冷菌多样性, 嗜冷菌群落结构, SMRT测序, 功能预测