Questions tagged [bacteria]

One of the three domains of life, with Archaea and eukaryotes. Bacteria, along with Archaea, are prokaryotes, i.e. lack a nucleus.

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Should I expect / use a prokaryote-specific substitution model when building a phylogenetic tree?

I have a couple of prokaryotic genes that I'm trying to build phylogenetic trees from. I inputted them into IQTree, which, as part of the workflow, runs through multiple substitution models until it ...
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How can I improve or otherwise investigate an unreliable genome tree?

Summary My genome tree doesn't agree with my gene trees and I get the feeling that my genome tree might be wrong, possibly due to long branch attraction, but I don't know how to check/fix it. ...
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Questions about microbial 16s rRNA phylogenetic, ANI Taxonomy, and GGDC

I have a few questions about these three methods. We commonly use 16s rRNA to identify species and construct a phylogenetic tree. If there's a new isolate from a new and undiscovered ecosystem, ...
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How to display novel genome assemblies or uncommon genome assemblies using the UCSC Genome Browser?

I want to display E.coli BW25113 (GenBank: CP009273.1) strain in UCSC browser. This strain is not listed in http://microbes.ucsc.edu/ browser. How can I display E.coli BW25113 assembly in the browser?
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Evolutionary speaking, what are the constraints on having new mutations?

Evolutionary speaking, some mutations lead to better fitness of an organism and its adaptation to the environment changes, but I was wondering if there are some constraints on having new mutations. ...
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How to modify dot plot in MUMmer 3 for bacteria comparative genomics?

I was trying to make a dotplot to visualize genome-genome sequence alignment by using the MUMmer 3 software (it is typically used to compare whole genome sequences of bacteria). I runned the same ...
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Search for specific sequence in group of bacterial genomes

I have a group of L. plantarum genomes. I identified the pangenome using Roary. From the pangenome, I was able to identify unique 'genes' for some of the strains. One of these (actually several were, ...
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Bruker MALDI-TOF bacteria species identification scoring algorithm

Just wondering whether anyone can point me to a research paper which describes how the scoring values are generated by the Bruker software for species identification of bacteria in MALDI-TOF MS. For ...
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What is the typical host-to-bug DNA ratio found in nanopore sequencing without amplification?

I'm interested in sequencing human sputum sample (typically used for TB and SARS-CoV-2 using an ONT MinION without performing any type of whole genome DNA amplification or targeted PCR. Has anyone ...
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How can I get or create a reference genome for Bacteria?

I am a computer engineer and nowadays trying to grasp some concepts of Bioinformatics particularly, reference genomes and genomic variants. My aim is to find the effect of sequence features on variant ...
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Populations genetics and dynamics of bacteria on a Graph

Disclaimer: I'm a physicist and I'm fairly new to Bioinformatics therefore somethings below may not make sense. My purpose: I would like to simulate genetic evolution of bacterial populations, ...
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How to fragment genomes into non-overlapping sequences of differing sizes?

I have bacterial chromosomes/plasmids that I have downloaded off refseq in a multi-fasta that I would like to fragment into non-overlapping fragments of between 1 kb and 15 kb. I have tried googling ...
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Bacterial DNA at the tail of transcriptome reads. What does that mean?

I am assembling a transcriptome obtained from the Internet. The transcriptome was extracted from a human cancer tissue that had been previously grafted into a mouse. I have detected that many ...
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What is the origin of the 'source Gene ID' references given in the 'gene_presence_absence.csv' output of Roary?

I am learning to use Roary for preparing a pan genome for some lactobacillus strains. In the 'gene_presence_absence.csv' output of Roary (which I view in excel), a 'source Gene ID' is given for each ...
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Visualizing cell growth

I model the following events: a rod-shaped cell with center $x$ grows symmetrically until it reaches a maximum length/age, it divides into two identical cells, and the process continues. At division, ...
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2 votes
1 answer
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How to construct the phylogenetic tree of the "High Recombination" genus streptomyces?

I need to construct the phylogenetic tree of the whole genus of streptomyces. And my goal is to find out how my target strep species distributed in the whole strep genus and obtain the distribution ...
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How many single copy gene are needed to construct the phylogenetic tree?

I ran the orthomcl program with genomes of the whole streptomyces genus(from ncbi) as input, but I only got 22 orthologous groups(streptomyces's genome size vary from 2M to 15M, which shows the great ...
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Looking for a tool to find 16S rRNA in hundreds of genomes

I have hundreds of bacterial genomes and I would like to know which is the best informatic tool in which I can run all genomes on one go and get a 16S rRNA gene sequence of each genome as output. ...
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2 answers
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Is there a "definitive" database for Mobile Genetic Elements?

This isn't quite my speciality, but I've been tasked with finding any evidence of Mobile Genetic Elements (like transposable elements, retrotransposons, bacteriophages, etc.) within some WGS samples. ...
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16S species-level taxonomic assignment--what is the current state of the art?

We currently use DADA2 for picking ASVs and the assignTaxonomy funciton for assingment to genera. Google does bring up various recent articles on species-level ...
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Extract reads from bam files by their @RG

How could I extract reads from bam files by their read groups @RG ?, I've got one file containing all reads for 5 samples, the SM is appears NONE, So, I want to extract each sample reads by the @RG ...
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Annotating conserved protein domains in bacterial assemblies

I understand the basic principles under which RPS-BLAST operates: search a protein (rpsblast) or nucleotide (rpstblastn) query ...
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Why is Clostridium difficile toxin A + B outdated in snomed?

I'm looking at the new version of the Snomed dictionary and the concept 707993000 Clostridium difficile toxin A + B (substance) is deactivated (and outdated) since ...
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how do I predict bacterial small non-coding RNA for a specific mRNA?

I am working on Vibrio parahaemolyticus. I have a gene that it is possible might be regulated by small non-coding RNAs. How can I predict possible sRNAs that target the transcript of this gene. Most ...
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5 votes
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CRISPR Sequence Finder and Database Download

I am searching for tools to pull CRISPR Spacers from Bacterial Genomes. I am aware of the CRISPRDB and the corresponding identification tool on the web server. Are there other tools for finding ...
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4 votes
2 answers
273 views

Gene function annotation - bacterial genome

I'm trying to annotate a genome to find all genes with a specific function. I have a FASTA and the read FASTQs - I'd like to assign the functional group of the identified proteins (e.g. Kegg orthology)...
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