Annotation:

spacer -> phage genome databese:
A viral reference database has been built for CRISPRs anlysis, it includes 10230 complete phage genomes from ncbi refSeq database. Putative protospacer targets will be identified by a BLASTN search of the spacer input against the viral reference database(default:coverage>=0.9), phage_ncbi_refseq_def_info.txt

phage genome -> spacer database:
Two spacer reference database has been built for CRISPRs anlysis, one only contains the complete bacteria genomes from NCBI, and the other includes the complete bacteria genomes and WGS bacteria genomes from NCBI.The best matching bacteria, which is obtained by aligning phage sequence gathered through user input to the spacer reference database(default:coverage>=0.9), is selected as the host of the predicted phage,all-bacteria-spacer.spc.

bacteria genome -> spacer -> phage genome:
Identify the spacer sequence from the bacteria sequence gathered from user input.
Determine whether the phage could infect the bacteria or not by aligning the identified spacer sequence to the phage sequence(default:coverage>0.9).