Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, USA.
New England Biolabs Inc, Ipswich, MA, USA.
Methods Mol Biol. 2021;2341:31-36. doi: 10.1007/978-1-0716-1550-8_5.
Staphylococcus aureus interacts with fibrinogen in plasma to form macroscopic clumps of cells. A simple and rapid slide agglutination test using rabbit plasma has been employed in clinical labs to distinguish S. aureus from most coagulase-negative Staphylococci. The method described here is a quantitative clumping assay in which S. aureus cells are mixed with either plasma or purified fibrinogen, and clumps are allowed to sediment out of solution. Clearing of the overlying solution is monitored over time by measuring the optical density at 600 nm and comparing these values to the initial turbidity. This simple assay can be used to study regulation and expression of various cell wall-anchored adhesins.
金黄色葡萄球菌在血浆中与纤维蛋白原相互作用,形成细胞的宏观聚集体。临床实验室采用一种简单快速的兔血浆玻片凝集试验来区分金黄色葡萄球菌和大多数凝固酶阴性葡萄球菌。这里描述的方法是一种定量的聚集测定法,其中将金黄色葡萄球菌细胞与血浆或纯化的纤维蛋白原混合,并允许聚集体从溶液中沉淀出来。通过测量 600nm 处的吸光度并将这些值与初始浊度进行比较,可以随时间监测上清液的澄清度。这种简单的测定法可用于研究各种细胞壁锚定黏附素的调节和表达。