Wednesday, July 24, 2013

Crystal structure of latex oxygenase RoxA

To date, two types of enzymes that are responsible for primary attack of polyisoprene in rubber-degrading microorganisms have been identified [1]. One is the latex clearing protein (Lcp), first isolated from Streptomyces sp., which does not have any metal ions or cofactors [2]. The other is the rubber oxygenase RoxA of Xanthomonas sp., a dihaem c-type cytochrome that cleaves cis-1,4-polyisoprene, the main constituent of natural rubber, to 12-oxo-4,8-dimethyltrideca-4,8-diene-1-al [3, 4]. The crystal structure of RoxA, solved at 1.8 Å resolution, was released today [5].

Latex Oxygenase RoxA @ PDB
  1. Birke, J., Hambsch, N., Schmitt, G., Altenbuchner, J. and Jendrossek, D. (2012) Phe317 is essential for rubber oxygenase RoxA activity. Applied and Environmental Microbiology 78, 7876—7883.
  2. Rose, K., Tenberge, K.B. and Steinbüchel, A. (2005) Identification and characterization of genes from Streptomyces sp. strain K30 responsible for clear zone formation on natural rubber latex and poly(cis-1,4-isoprene) rubber degradation. Biomacromolecules 6, 180—188.
  3. Braaz, R., Fischer, P. and Jendrossek, D. (2004) Novel type of heme-dependent oxygenase catalyzes oxidative cleavage of rubber (poly-cis-1,4-isoprene). Applied and Environmental Microbiology 70, 7388—7395.
  4. Schmitt, G., Seiffert, G., Kroneck, P.M.H., Braaz, R. and Jendrossek, D. (2010) Spectroscopic properties of rubber oxygenase RoxA from Xanthomonas sp., a new type of dihaem dioxygenase. Microbiology 156, 2537—2548.
  5. PDB:4B2N