DNA的分子量估算

核酸、核苷酸的基本换算1．核酸的换算： (1)摩尔数与质量： 1 μg 1,000bp DNA = 1.52 pmol 1 μg pUC18/19 DNA (2,688bp) = 0.57 pmol 1 μg pBR322 DNA (4,361bp) = 0.35 pmol 1 μg SV40 DNA (5,243bp) = 0.29 pmol 1 μg FX174 DNA (5,386bp) = 0.28 pmol 1 μg M13mp18/19 DNA (7.250bp) = 0.21 pmol 1 μg l phage DNA (48,502bp) = 0.03 pmol 1 pmol 1,000bp DNA = 0.66 μg 1 pmol pUC18/19 DNA (2,688bp) = 1.77 μg 1 pmol pBR322 DNA (4,361bp) = 2.88 μg 1 pmol SV40 DNA (5,243bp) = 3.46 μg 1 pmol FX174 DNA (5,386bp) = 3.54 μg 1 pmol M13mp18/19 DNA (7.250bp) = 4.78 μg 1 pmol l phage DNA (48,502bp) = 32.01 μg (2)光吸收值与浓度： 1 OD260 dsDNA = 50 μg/ml = 0.15 mmol/L 1 OD260 ssDNA = 33 μg/ml = 0.10 mmol/L 1 OD260 ssRNA = 40 μg/ml = 0.12 mmol/L 1 mmol/L dsDNA = 6.7 OD260 1 mmol/L ssDNA = 10.0 OD260 1 mmol/L ssRNA = 8.3 OD260 (3)分子量： 1个脱氧核糖核酸碱基的平均分子量为333 Daltons 1个核糖核酸碱基的平均分子量为340 Daltons (4)核酸末端浓度： 环状DNApmol ends = pmol DNA × number of cuts ×2线性DNApmol ends = pmol DNA ×(number of cuts ×2 + 2) 1 μg 1,000 bp DNA = 3.04 pmol ends 1 μg pUC18/19 DNA (2,68