Katouli M, Kühn I, Wollin R, Möllby R
Department of Bacteriology, Karolinska Institute, Stockholm, Sweden.
J Med Microbiol. 1992 Oct;37(4):245-51. doi: 10.1099/00222615-37-4-245.
The Phene Plate (PhP) system of biochemical fingerprinting of bacteria is a computerised typing system, based on quantitative measurements of the kinetics of several biochemical reactions of bacteria grown in liquid medium in microtitration plates. For each isolate tested, it yields a biochemical fingerprint comprising several kinds of quantitative data which are useful for establishing similarities among strains with a personal-computer program. In this study, a set of 16 specific substrates was chosen to differentiate strains of Salmonella of serotype Typhimurium. The system was evaluated for its typability, reproducibility and discriminatory power in tests with a collection of 100 epidemiologically unrelated Typhimurium strains and results were compared with those obtained by phage typing. At an identity level of 0.980, strains were assigned by this method to 51 biochemical phenotypes (BPTs), giving a diversity index of 0.963 and a resolution index of 0.210. In contrast, 24 phage types (PTs) were identified among these isolates (a diversity index of 0.901). The combined use of biochemical fingerprinting by the PhP system and phage typing discriminated 82 phenotypes (a diversity index of 0.994). Stability of markers in each of the methods was also evaluated after subculture of 20 strains for 21 consecutive days. Only nine biochemical reactions were found that were subject to small, but measurable, changes for at least one isolate. These changes slightly decreased the mean similarity coefficients among strains but the overall BPTs of the strains showed changes in four strains (20%). In contrast, eight strains (40%) showed changes in their PTs after this treatment. It is concluded that the PhP system is a highly discriminatory and reproducible method for typing Typhimurium strains. It is easy to perform, and may be used alone or in combination with phage typing in epidemiological studies of Typhimurium strains.
细菌生化指纹图谱的芬尼平板（PhP）系统是一种计算机化分型系统，基于对微量滴定板中液体培养基中生长的细菌的几种生化反应动力学的定量测量。对于每个测试的分离株，它会产生一个生化指纹图谱，其中包含几种定量数据，这些数据可用于通过个人计算机程序确定菌株之间的相似性。在本研究中，选择了一组16种特定底物来区分鼠伤寒血清型沙门氏菌菌株。该系统在对100株流行病学无关的鼠伤寒菌株进行测试时，对其分型能力、可重复性和鉴别力进行了评估，并将结果与噬菌体分型获得的结果进行了比较。在同一性水平为0.980时，通过该方法将菌株分为51种生化表型（BPT），多样性指数为0.963，分辨率指数为0.210。相比之下，在这些分离株中鉴定出24种噬菌体类型（PT）（多样性指数为0.901）。PhP系统的生化指纹图谱和噬菌体分型的联合使用区分出82种表型（多样性指数为0.994）。在对20株菌株连续传代培养21天后，还评估了每种方法中标记物的稳定性。仅发现9种生化反应至少对一种分离株有微小但可测量的变化。这些变化略微降低了菌株之间的平均相似系数，但菌株的总体BPT在4株菌株（20%）中显示出变化。相比之下，8株菌株（40%）在此处理后其PT显示出变化。结论是，PhP系统是一种用于鼠伤寒菌株分型的高度鉴别性和可重复的方法。它易于操作，可单独使用或与噬菌体分型联合用于鼠伤寒菌株的流行病学研究。
