Reaction: Cleavage of cis-1,4-polyisoprene polymers into a mixture of compounds, including a C20 compound ((4Z,8Z,12Z,16Z,20Z,24Z)-4,8,12,16,20,24-hexamethyl-28-oxononacosa-4,8,12,16,20,24-hexaenal), a C25 compound ((4Z,8Z,12Z,16Z,20Z)-4,8,12,16,20-pentamethyl-24-oxopentacosa-4,8,12,16,20-pentaenal), a C30 compound ((4Z,8Z,12Z,16Z)-4,8,12,16-tetramethyl-20-oxohenicosa-4,8,12,16-tetraenal), and larger isoprenologes such as C35, C40, C45, and higher analogues.
For diagram of reaction click here.
Other name(s): latex clearing protein; lcp (gene name); roxB (gene name)
Systematic name: cis-1,4-polyisoprene:oxygen dioxygenase (endo-cleaving)
Comments: The enzyme catalyses the cleavage of the double bonds in natural and synthetic rubber, producing a mixture of C20, C25, C30, and higher oligo-isoprenoids with ketone and aldehyde groups at their ends. Two unrelated bacterial enzymes are known to possess this activity - the enzyme from Streptomyces sp. K30 (Lcp) contains a b-type cytochrome, while the enzyme from Xanthomonas sp. 35Y, (RoxB) contains two c-type cytochromes. Both enzymes attack the substrate at random locations, and are not able to cleave the C35 or smaller products into shorter fragments.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
1. Tsuchii, A. and Takeda, K. Rubber-degrading enzyme from a bacterial culture. Appl. Environ. Microbiol. 56 (1990) 269-274. [PMID: 16348100]
2. Jendrossek, D. and Reinhardt, S. Sequence analysis of a gene product synthesized by Xanthomonas sp. during growth on natural rubber latex. FEMS Microbiol. Lett. 224 (2003) 61-65. [PMID: 12855168]
3. Braaz, R., Fischer, P. and Jendrossek, D. Novel type of heme-dependent oxygenase catalyzes oxidative cleavage of rubber (poly-cis-1,4-isoprene). Appl. Environ. Microbiol. 70 (2004) 7388-7395. [PMID: 15574940]
4. Braaz, R., Armbruster, W. and Jendrossek, D. Heme-dependent rubber oxygenase RoxA of Xanthomonas sp. cleaves the carbon backbone of poly(cis-1,4-Isoprene) by a dioxygenase mechanism. Appl. Environ. Microbiol. 71 (2005) 2473-2478. [PMID: 15870336]
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6. Birke, J. and Jendrossek, D. Rubber oxygenase and latex clearing protein cleave rubber to different products and use different cleavage mechanisms. Appl. Environ. Microbiol. 80 (2014) 5012-5020. [PMID: 24907333]
7. Birke, J., Röther, W. and Jendrossek, D. RoxB is a novel type of rubber oxygenase that combines properties of rubber oxygenase RoxA and latex clearing protein (Lcp). Appl. Environ. Microbiol. 83 (2017) e00721-17. [PMID: 28500046]