An operational taxonomic unit (OTU) is an operational definition used to classify groups of closely related individuals. The term was originally introduced in 1963 by Robert R. Sokal and Peter H. A. Sneath in the context of numerical taxonomy, where an "operational taxonomic unit" is simply the group of organisms currently being studied. [1] .

In a recent paper, Westcott and Schloss proposed a definition of OTUs based on the Matthews Correlation Coefficient (MCC). However, their definition has problems in practice. Here, I suggest some goals for making OTUs. Sneath-Sokal classification of the sequences. This is the historical motivation for making 16S OTUs.

Operational taxonomic unit or OTU is considered as the basic unit used in numerical taxonomy. These units may refer to an individual, species, genus, or class. In numerical methods, the taxonomic units used are constantly not comparable to the formal taxonomic units.

The OTUX (meta)database consists of 19 distinct OTU databases corresponding to the different stretches of variable regions (V-regions) of the bacterial 16S rRNA gene, that are commonly targeted for amplicon sequencing in microbiome studies.

Aug 18, 2013 · To determine microbial community structure, the UPARSE software extracts operational taxonomic unit (OTU) representative sequences with high accuracy on the basis of amplified marker-gene...

OTU's are used to categorize bacteria based on sequence similarity. In 16S metagenomics approaches, OTUs are cluster of similar sequence variants of the 16S rDNA marker gene sequence. Each of these cluster is intended to represent a taxonomic unit of a bacteria species or genus depending on the sequence similarity threshold.

See defining and interpreting OTUs for discussion. With 97% clustering, an OTU sequence should be at least 3% different from all other OTUs, and should be the most abundant sequences in its neighborhood. This is done by the cluster_otus command, which is an implementation of the UPARSE algorithm.

When we cannot determine whether a sequence has come from a distinctive species, we can describe the fungus as an operational taxonomic unit (OTU). An OTU can refer to any stipulated level of the taxonomic hierarchy, ranging from populations …

Apr 20, 2016 · Sequences are clustered into bins called ‘Operational Taxonomic Units’ (OTUs) based upon similarity. Typically, the similarity between a pair of sequences is computed as the percentage of...

An operational taxonomic unit (OTU) is a term used in DNA-based sequencing techniques to represent the number of taxonomic units identified in a given sample. OTUs are defined at a certain level of similarity and are often clustered against a reference database.