生化中的E-value是什么意思?特别是在关于酶的文献中常见.

生化中的E-value是什么意思?特别是在关于酶的文献中常见.

不止是酶学,这是个统计上常用的,表明随机匹配的概率,这个值越小,说明结果越可靠.
再问： 可是，这句The immobilization of A.niger EH on epoxy-activated supports modified with ethylene diamine enhanced the E-value from 25 to 56 for enantioselective hydrolysis of racemic styrene oxide。我将其翻译为：“将A.niger（一种菌） EH（环氧水解酶）固定在乙二胺修饰的环氧活化载体上可以使其对外消旋环氧苯乙烷的立体选择性水解的E-value从25增加到56。”
再答： NCBI上关于它的解释： Q: What is the Expect (E) value? The Expect value (E) is a parameter that describes the number of hits one can "expect" to see by chance when searching a database of a particular size. It decreases exponentially as the Score (S) of the match increases. Essentially, the E value describes the random background noise. For example, an E value of 1 assigned to a hit can be interpreted as meaning that in a database of the current size one might expect to see 1 match with a similar score simply by chance. The lower the E-value, or the closer it is to zero, the more "significant" the match is. However, keep in mind that virtually identical short alignments have relatively high E values. This is because the calculation of the E value takes into account the length of the query sequence. These high E values make sense because shorter sequences have a higher probability of occurring in the database purely by chance. For more details please see the calculations in the BLAST Course. The Expect value can also be used as a convenient way to create a significance threshold for reporting results. You can change the Expect value threshold on most BLAST search pages. When the Expect value is increased from the default value of 10, a larger list with more low-scoring hits can be reported.