TABLE 2.

Substrate specifities of chloromuconate cycloisomerases from different strainsa

Strain and substrateKm (μM)kcat (min−1)kcat/Km (μM−1 min−1)Relative specifity constant (%)Relative activity at 0.1 mM substrate (%)
Ralstonia sp. strain PS12
    cis,cis-Muconateb239780.33935
    2-Chloro-cis,cis-muconate1461220.842470
    3-Chloro-cis,cis-muconate1891710.9026100
    2,4-Dichloro-cis,cis-muconate911611.132165
    2-Methyl-cis,cis-muconatec1002312.3166186
    3-Methyl-cis,cis-muconated2588983.48100448
    2,5-Dichloro-3-methyl-cis,cis-muconateNDeNDNDND151
    2,4-Dichloro-5-methyl-cis,cis-muconateND NDNDND46
    2,3-Dichloro-5-methyl-cis,cis-muconateND NDNDND43
Pseudomonas sp. strain B13
    cis,cis-Muconate2714811.81215
    2-Chloro-cis,cis-muconate42481117439
    3-Chloro-cis,cis-muconate1592,2401492100
    2,4-Dichloro-cis,cis-muconate263941510036
    2-Methyl-cis,cis-muconate917448.25445
    3-Methyl-cis,cis-muconate324811510042
    2,5-Dichloro-3-methyl-cis,cis-muconateND NDNDND167
    2,4-Dichloro-5-methyl-cis,cis-muconateND NDNDND31
    2,3-Dichloro-5-methyl-cis,cis-muconateND NDNDND82
Ralstonia sp. strain JMP134
    cis,cis-Muconate9967040.710.583
    2-Chloro-cis,cis-muconate792152.72.26
    3-Chloro-cis,cis-muconate983,77038.032100
    2,4-Dichloro-cis,cis-muconate232,810120.0100120
    2-Methyl-cis,cis-muconate3125,44017.01469
    3-Methyl-cis,cis-muconate523,46066.055120
    2,5-Dichloro-3-methyl-cis,cis-muconateND NDNDND76
    2,4-Dichloro-5-methyl-cis,cis-muconateND NDNDND25
    2,3-Dichloro-5-methyl-cis,cis-muconateND NDNDND20
Pseudomonas sp. strain P51
    cis,cis-Muconate1773832.2131
    2-Chloro-cis,cis-muconate584077.11358
    3-Chloro-cis,cis-muconate1841,2606.913100
    2,4-Dichloro-cis,cis-muconate1997853.0100185
    2-Methyl-cis,cis-muconate921,50016.031176
    3-Methyl-cis,cis-muconate1451,0707.41498
  • a The data for strains B13, JMP134, and P51 are from reference 67, except for the relative activity values for the dichloromethylmuconates.

  • b For cis,cis-muconate, ε299 = 457 M−1 cm−1 (67). Substrate concentrations were 0.2 to 0.9 mM.

  • c For 2-methyl-cis,cis-muconate, ε285 = 6,050 M−1 cm−1 (67). Substrate concentrations were 0.025 to 0.2 mM.

  • d For 3-methyl-cis,cis-muconate, ε280 = 5,050 M−1 cm−1. Substrate concentrations were 0.05 to 0.35 mM.

  • e ND, not done.