Abstract: Provided is a method and a device for screening an antigen epitope polypeptide. The screening method includes: predicting one or more antigen epitopes with all proteome sequences of a target coronavirus to obtain a predicted epitope region; screening a polypeptide with a differential response to a positive serum sample infected by the target coronavirus and a control serum sample with a polypeptide chip technology, and recording the polypeptide as a differential peptide fragment; comparing the differential peptide fragment with all proteome sequences of the target coronavirus to obtain a first conserved motif region; screening regions meeting epitope screening conditions from the predicted epitope region and the first conserved motif region to obtain the antigen epitope, wherein the epitope screening conditions comprise a non-phosphorylation region and/or an extracellular region of the target coronavirus.

Abstract: Provided is a method of gap closing in nucleotide sequence. The nucleic acid sequence comprises a first contig at one end of a gap in an unassembled region, and a second contig at the other end of the gap in the unassembled region.

Abstract: Provided is a method of acquiring genome size. The method comprises steps of sequencing random fragments of whole genome, acquiring all of k-mer information including k-mer depth, counting frequency of each k-mer depth value so as to determine expected k-mer depth, and acquiring the genome size by dividing the sum of k-mers by the expected k-mer depth. The method is convenient, rapid, and cost-effective. Also provided is a method of acquiring error of sequencing genome based on all of k-mer information including k-mer depth.