zZ format is typically composed by zZ+unique id or accesscion+zZ (e.g. zZCP001758zZ or zZ12494zZ). These zZ-formatted labels are used in plain text files such as newick format for phylogenetic trees and dendrograms. In fact, any text files can be used in the same way.
zZ-format is used because of two reasons. First, some software tools can not handle the complicated form of labels. For example, some phylogenetic treeing software can not infer phylogenetic trees with the label “Leuconostoc kimchii IMSNU 11154(T)/CP001758”. In this case, we can employ zZCP001758zZ as a sequence label, then change it later to the full format. Second, once we calculate phylogenetic tree which may take very long time, we can change sequence labels with desired formats. In this case, zZCP001758zZ can be changed to either “Leuconostoc kimchii”, “IMSNU 11154” or “Leuconostoc kimchii IMSNU 11154(T)/CP001758”. zZ-formatted files describing phylogenetic trees and multiple sequence alignments are often used in the EzBioCloud and BIOiPLUG services. The re-formatting feature is available from http://www.ezbiocloud.net/tools/labelreplacer.
The below shows an example of using zZ-formatted newick file to replace labels to different formats: