Information literate students with a good understanding of science are regarded as an important pool of future successful professionals. The study explored correlations between the information literacy (IL) and scientific literacy (SL) of university students and analysed their achievements according to Bloom's cognitive categories of remembering, understanding and applying knowledge. A theoretical connection between IL standards and SL competencies was exposed. An information literacy test and a science literacy test, derived from the PISA 2006 science scale, were used for assessment. The results showed a significant moderate positive correlation between students' SL and IL. Students with a better understanding of science were more successful in all three cognitive levels of IL, and students with higher SL scores were better in the application of IL knowledge. A specialised credit-bearing IL course with active learning significantly improved the IL level of all students, most notably in applying IL knowledge, and thus reduced the initial IL disparities between students with low and high SL. The study brought the realisation that the IL of university students depends on their SL obtained in previous education; however, a well-designed university IL course contributes towards higher cognitive levels of IL for all students.