Thiostrepton (tpdA) Recombinant Protein

Function: Has bacteriocidal activity. Inhibits bacterial protein biosynthesis by acting on the elongation factor Tu (EF-Tu)

By similarity.

Subcellular location: Secreted

By similarity.

Post-translational modification: Maturation of thiazole and oxazole containing antibiotics involves the enzymic condensation of a Cys, Ser or Thr with the alpha-carbonyl of the preceding amino acid to form a thioether or ether bond, then dehydration to form a double bond with the alpha-amino nitrogen. Thiazoline or oxazoline ring are dehydrogenated to form thiazole or oxazole rings.Maturation of pyridinyl containing antibiotics involves the cross-linking of a Ser and a Cys-Ser pair usually separated by 7 or 8 residues along the peptide chain. The Ser residues are dehydrated to didehydroalanines, then bonded between their beta carbons. The alpha carbonyl of the Cys condenses with alpha carbon of the first Ser to form a pyridinyl ring. The ring may be multiply dehydrogenated to form a pyridine ring with loss of the amino nitrogen of the first Ser.The amidation of Ser-72 probably does not occur by the same mechanism, oxidative cleavage of glycine, as in eukaryotes.The structure of the 2,3-didehydrobutyrin is shown to be Z-isomer (Ref.8 and Ref.10).

Pharmaceutical use: Available under the names Animax (Dechra) and Panolog (Fort Dodge), that combine thiostrepton with nystatin (antifungal), neomycin (antibiotic) and triamcinolone (corticosteroid). Used to treat cat and dog skin and ear disorders caused by allergies, or bacterial as well as yeast infections. It is also used for infections of the anal gland and interdigital cysts.

Sequence similarities: Belongs to the thiocillin family.

Caution: Thiostrepton is produced by Streptomyces azureus 14921, S.hawaiiensis 12236, and by S.laurentii 31255. The species used as a thiostrepton producer in all studies is uncertain.It is uncertain whether Met-1 or Met-13 is the initiator.