The following bacterial proteins, which seems to belong to a family of pseudouridine synthases (EC 5.4.99.-) [1] have been shown to share regions of similarities:

• Escherichia coli and Haemophilus influenzae 16S pseudouridylate 516 synthase (EC 5.4.99.-) (gene: rsuA). This enzyme is responsible for the formation of pseudouridine from uracil-516 in 16S ribosomal RNA.
• Escherichia coli and Haemophilus influenzae ribosomal large subunit pseudouridine synthase B (rluB).
• Bacillus subtilis ribosomal large subunit pseudouridine synthase B (rluB).
• Escherichia coli ribosomal large subunit pseudouridine synthase F (rluF).
• Escherichia coli and Haemophilus influenzae ribosomal large subunit pseudouridine synthase E (rluE).
• Aquifex aeolicus hypothetical protein AQ_554.
• Aquifex aeolicus hypothetical protein AQ_1464.
• Bacillus subtilis hypothetical protein ytzF.
• Borrelia burgdorferi hypothetical protein BB0129.
• Helicobacter pylori hypothetical protein HP1459.
• Synechocystis strain PCC 6803 hypothetical protein slr0361.
• Synechocystis strain PCC 6803 hypothetical protein slr0612.

These are proteins of from 25 to 40 Kd which contain a number of conserved regions in their central section. They can be picked up in the database by the following highly conserved pattern.