BOL: LEGE's News

New BLAST Core Nucleotide Database (core_nt)

LEGE — Tue, 13 Aug 2024 07:12:53 -0500

The Core Nucleotide Database (core_nt) is now the default nucleotide BLAST database. Core_nt is also available on the command line. You get faster searches & more focused results.

Core_nt contains the same eukaryotic transcript and gene-related sequences as nt. The core_nt database is nt without most eukaryotic chromosome sequences. Most nucleotide BLAST searches with core_nt will be similar to the nt database. However, core_nt is better than nt for accomplishing your most common BLAST search goals, such as identifying gene-related sequences like transcript sequences and complete bacterial chromosomes. This is because, in recent years, nt has acquired more low-relevance, non-annotated, and non-gene content.

Learn more: https://ncbiinsights.ncbi.nlm.nih.gov/2024/07/18/new-blast-core-nucleotide-database/

Cleaner BLAST Databases for More Accurate Results

LEGE — Tue, 23 Apr 2024 01:23:08 -0500

Do you use BLAST to identify a sequence or the evolutionary scope of a gene? That can be challenging if contaminated and misclassified sequences are in the BLAST databases and show up in your search results. To address this problem, we now use the NCBI quality assurance tools listed below to systematically remove these misleading sequences from the default nucleotide (nt) and protein (nr) BLAST databases.

Foreign Contamination Screen tool for genome cross-species screening (FCS-GX) detects contamination from foreign organisms in genomes and other sequences using the genome cross-species aligner (GX)
Average Nucleotide Identity (ANI) evaluates the taxonomic classification of prokaryotic genome assemblies. Sequences from genomes marked up as ‘unverified source organism’ are considered suspect and removed.

Ref https://ncbiinsights.ncbi.nlm.nih.gov/2024/04/22/cleaner-blast-databases-more-accurate-results/

Blast on Docker, Google Cloud, Amazon Cloud

LEGE — Thu, 09 Jul 2020 02:57:11 -0500

As announced in a previous post, we offer a Docker version of NCBI BLAST+ that you can use locally or on the Google Cloud where we have pre-loaded BLAST databases. We are happy to announce that the same functionality is now available on the Amazon Cloud. In addition, we now offer 23 different BLAST databases on each cloud platform.

As mentioned before, working with BLAST+ in Docker and the cloud has several advantages:

Docker manages installation and maintenance of the BLAST programs and databases.
Docker makes it is easier to integrate BLAST with other tools in your pipelines.
NCBI BLAST databases are pre-loaded now on the both the Google Cloud and Amazon Cloud, providing fast access.

You can also use the BLAST+ Docker image on any Docker-enabled platform, such as another cloud platform or on your local computer.

See the BLAST+ in the Cloud and database information documentation to get started.

If you have any questions, please email us at blast-help@ncbi.nlm.nih.gov

Source:Dave Arndt