Goodgal S H, Mitchell M
J Bacteriol. 1984 Mar;157(3):785-8. doi: 10.1128/jb.157.3.785-788.1984.
With the use of highly competent Haemophilus influenzae cells, it was possible to demonstrate the uptake of heterologous DNAs. However, these DNAs, as expected, were only 1% or less as effective when competing for uptake with Haemophilus DNA. Escherichia coli DNA was removed from solution by competent cells to the extent expected if all the E. coli DNA particles contained at least one uptake recognition signal. The data were consistent with a model in which there was one uptake signal per 20 X 10(6) to 30 X 10(6) daltons of E. coli DNA. Since H. influenzae DNA has many more recognition signals, approximately one per 2 X 10(6) daltons (Danner et al., Gene 77:311-318, 1980; K. Vogt and S. H. Goodgal, submitted for publication), it has been suggested that the slower rate of E. coli DNA binding and the so-called specificity of Haemophilus DNA binding are due to the number of recognition signals per molecule of DNA as well as the nature of the DNA receptor (Vogt and Goodgal, submitted for publication). The specificity of native H. influenzae DNA binding does not apply to the uptake of denatured DNA in the transforming system (low pH) for denatured DNA.
利用高度感受态的流感嗜血杆菌细胞，能够证明异源DNA的摄取。然而，正如预期的那样，这些DNA在与流感嗜血杆菌DNA竞争摄取时，其有效性仅为1%或更低。感受态细胞从溶液中去除大肠杆菌DNA的程度，与如果所有大肠杆菌DNA颗粒都至少含有一个摄取识别信号时预期的程度一致。数据与一个模型相符，即每20×10⁶至30×10⁶道尔顿的大肠杆菌DNA有一个摄取信号。由于流感嗜血杆菌DNA有更多的识别信号，大约每2×10⁶道尔顿有一个（丹纳等人，《基因》77:311 - 318，1980；K. 沃格特和S. H. 古德加尔，待发表），有人提出大肠杆菌DNA结合速率较慢以及流感嗜血杆菌DNA结合的所谓特异性，是由于每分子DNA的识别信号数量以及DNA受体的性质（沃格特和古德加尔，待发表）。天然流感嗜血杆菌DNA结合的特异性不适用于变性DNA转化系统（低pH）中变性DNA的摄取。
