### Make Bin Directory Executable

Source: https://github.com/davidchyou/crisprtarget/blob/main/README.md

Ensure all dependency executables in the 'bin' directory are executable by running this command. This is a prerequisite for using the CRISPRTarget script.

```bash
chmod -R 777 bin
```

--------------------------------

### Build BLASTDB and Search with Database Size (Use Case 2)

Source: https://github.com/davidchyou/crisprtarget/blob/main/README.md

Similar to Use Case 1, this command builds BLAST databases and indices. It includes the '-dbsize' option to specify the database size for statistical analysis, allowing for comparable P-values across different database sizes. Use this when generating databases and performing the initial search.

```perl
perl CRISPRTarget.pl -gff sample_crispr_gff/PSA.crispr.gff -user_fasta sample_db/vhdb_selected.fna -dbsize 100000000 -evalue 1 -out test_out -pam_search_all
```

--------------------------------

### Build BLASTDB and Search for Targets (Use Case 1)

Source: https://github.com/davidchyou/crisprtarget/blob/main/README.md

This command builds a BLAST database and index for genomic sequences, shuffles them, builds another BLASTDB and index for the shuffled sequences, and then searches for CRISPR-spacer targets. Use this when you have a GFF file and FASTA files for your target genomes and want to generate databases from scratch.

```perl
perl CRISPRTarget.pl -gff sample_crispr_gff/PSA.crispr.gff -user_fasta DB/phage.fa -evalue 0.1 -out phage_out -pam_search_all
```

--------------------------------

### Search with Pre-computed BLASTDBs (Use Case 3)

Source: https://github.com/davidchyou/crisprtarget/blob/main/README.md

This command searches for CRISPR-spacer targets and computes P-values using pre-computed BLAST databases and their indices for both the genomes and the shuffled sequences. Use this when you have already generated and saved the necessary databases from previous runs.

```perl
perl CRISPRTarget.pl -gff sample_crispr_gff/PSA.crispr.gff -db USER_DB/vhdb_selected.fna -ctrl_db USER_SHUFFLED_DB/vhdb_selected.fna -dbsize 100000000 -evalue 1 -out test_out_2 -pam_search_all
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.