Dairy Foods, AgResearch, Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand.
SciLactis Ltd, Waikato Innovation Park, Hamilton, New Zealand.
Proteome Sci. 2014 Apr 11;12:19. doi: 10.1186/1477-5956-12-19. eCollection 2014.
Milk contains a range of proteins of moderate or low abundance that contribute to host defence. Characterisation of these proteins, the extent to which their abundance is regulated by pathogenic stimuli, and the variability of their response between and within individual animals would facilitate a better understanding of the molecular basis for this important function of milk.
We have characterised the host defence proteins in bovine milk and their responses to intra-mammary infection by a common Gram positive mastitis pathogen, Streptococcus uberis, using a combination of 2D gel electrophoresis and GeLC mass spectrometry. In total, 68 host defence-associated proteins were identified, 18 of which have a direct antimicrobial function, 23 of which have a pathogen-recognition function, and 27 of which have a role in modulating inflammatory or immune signalling. The responsiveness of seven proteins was quantified by western blotting; validating the proteomic analyses, quantifying the within- and between animal variability of the responses, and demonstrating the complexity and specificity of the responses to this pathogen.
These data provide a foundation for understanding the role of milk in host-microbe interaction. Furthermore they provide candidate biomarkers for mastitis diagnosis, and will inform efforts to develop dairy products with improved health-promoting properties.
牛奶中含有一系列中等或低丰度的蛋白质，这些蛋白质有助于宿主防御。这些蛋白质的特性、它们的丰度受致病刺激调节的程度以及它们在个体动物之间和内部的反应变异性，将有助于更好地理解牛奶这一重要功能的分子基础。
我们使用 2D 凝胶电泳和 GeLC 质谱联用技术，对牛初乳中的宿主防御蛋白及其对常见革兰氏阳性乳腺炎病原体乳链菌的反应进行了表征。总共鉴定出 68 种宿主防御相关蛋白，其中 18 种具有直接的抗菌功能，23 种具有病原体识别功能，27 种具有调节炎症或免疫信号的作用。通过 Western 印迹法对 7 种蛋白质的反应性进行了定量；验证了蛋白质组学分析，量化了反应的个体内和个体间变异性，并证明了对这种病原体的反应的复杂性和特异性。
这些数据为理解牛奶在宿主-微生物相互作用中的作用提供了基础。此外，它们为乳腺炎诊断提供了候选生物标志物，并将为开发具有改善健康促进特性的乳制品提供信息。
