Progress in bioengineering brought a new approach to DNA sequencing, which aim is to give highly reliable output of low cost and in short time. It is 454 sequencing, based on the pyrosequencing protocol, owned by 454 Life Sciences Corporation. Because of the sequences reliability this method is much better than others for assembly purposes. However, produced sequences are much shorter and there are many more of them, which indicate that the problem is harder. Presented algorithm was created to process data from 454 sequencing method. Usefulness of the algorithm has been proven in tests on raw data generated during sequencing of the whole 1.84 Mbp genome of bacteria Prochlorococcus marinus.