title: Site-specific restriction endonucleases in cyanobacteria.
abstract: OBJECTIVE
  Planktic cyanobacteria were screened for endodeoxyribonucleases. Principal component analysis (PCA) was employed to demonstrate a potential relationship between certain enzymes and a group of cyanobacteria. The data were obtained from a data bank and this study.
  
  
  RESULTS
  Enzymes were partially purified using column chromatography. Anabaena strains contained Asp83/1I (5'-TTCGAA-3'), Asp83/1II (5'-GGCC-3'), Asp90I (5'-ACRYGT-3') and five isoschizomeric enzymes (5'-ATCGAT-3'). Aphanizomenon and Microcystis strains contained ApcTR183I (5'-TGCGCA-3') and Msp199I (5'-CCGG-3'), respectively. Planktothrix strains possessed Psc2I (5'-GAANNNNTTC-3'), Psc27I and Psc28I (5'-TTCGAA-3'). PCA showed that the most common cyanobacterial endonuclease types were AvaII, AvaI and AsuII.
  
  
  CONCLUSIONS
  All planktic cyanobacteria studied contained restriction endonucleases. The defined restriction endonucleases were isoschizomers of known enzymes. The Nostoc and the Spirulina genera had an association, while the majority of the genera had no association with certain endonuclease type(s).
  
  
  CONCLUSIONS
  The defined enzymes in this study and the estimated trend in the endonuclease type distribution allow more efficient avoidance of cyanobacterial restriction barriers.
authors: Department of Applied Chemistry and Microbiology, Helsinki University, and Finnzymes Oy, Espoo, Finland.
authors: C
authors: C
authors: Lyra
authors: T
authors: T
authors: Halme
authors: A M
authors: AM
authors: Torsti
authors: T
authors: T
authors: Tenkanen
authors: K
authors: K
authors: Sivonen
mesh_terms: D017033:Anabaena / Q000201:enzymology; D000458:Cyanobacteria / Q000201:enzymology*; D015252:Deoxyribonucleases, Type II Site-Specific / Q000302:isolation & purification* / Q000378:metabolism*; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D007527:Isoenzymes; D015252:Deoxyribonucleases, Type II Site-Specific