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Literature summary extracted from

  • Zhan, D.; Bai, A.; Yu, L.; Han, W.; Feng, Y.
    Characterization of the PH1704 protease from Pyrococcus horikoshii OT3 and the critical functions of Tyr120 (2014), PLoS One, 9, e103902.
    View publication on PubMedView publication on EuropePMC

Cloned(Commentary)

EC Number Cloned (Comment) Organism
3.4.11.B7 expression in Escherichia coli Pyrococcus horikoshii
3.4.22.B78 DNA and amino acid sequence determination and analysis, phylogenetic tree, recombinant expression of wild-type and mutant enzymes in Escherichia coli strain BL21(DE3) Pyrococcus horikoshii
3.4.22.B78 expression in Escherichia coli Pyrococcus horikoshii

Protein Variants

EC Number Protein Variants Comment Organism
3.4.11.B7 Y120P kat and kat/Km of the mutant enzyme with L-Arg-7-amino-4-methylcoumarin are about 7 and 7.8times higher than that of the wild type enzyme, respectively Pyrococcus horikoshii
3.4.22.B78 Y120P with Ala-Ala-Phe-Arg-7-amido-4-methylcoumarin as substrate, kcat and kcat/Km is 10- and 21fold higher than that of the wild-type enzyme Pyrococcus horikoshii
3.4.22.B78 Y120P site-directed mutagenesis, the mutant shows highly increased activity compared to the wild-type enzyme Pyrococcus horikoshii

Inhibitors

EC Number Inhibitors Comment Organism Structure
3.4.11.B7 iodoacetamide strongly inhibits the peptidase activity, confirming that Cys100 is a nucleophilic residue Pyrococcus horikoshii
3.4.22.B78 Ca2+ inhibits 29% at 5 mM, 19% at 1 mM Pyrococcus horikoshii
3.4.22.B78 Co2+ inhibits 74% at 0.2 mM and precipitates the enzyme at 1 mM Pyrococcus horikoshii
3.4.22.B78 Cu2+ inhibits 57% at 0.2 mM, 81% at 1 mM, and precipitates the enzyme at 5 mM Pyrococcus horikoshii
3.4.22.B78 Fe3+ inhibits 28% at 0.2 mM, 68% at 1 mM, and precipitates the enzyme at 5 mM Pyrococcus horikoshii
3.4.22.B78 iodoacetamide strong inhibition; strongly inhibits the peptidase activity, confirming that Cys100 is a nucleophilic residue Pyrococcus horikoshii
3.4.22.B78 K+ inhibits 19% at 5 mM Pyrococcus horikoshii
3.4.22.B78 Mg2+ inhibits 10% at 5 mM Pyrococcus horikoshii
3.4.22.B78 Mn2+ inhibits 81% at 5 mM, 42% at 1 mM Pyrococcus horikoshii
3.4.22.B78 Na+ inhibits 28% at 5 mM Pyrococcus horikoshii
3.4.22.B78 Ni2+ inhibits 85% at 0.2 mM and precipitates the enzyme at 1 mM Pyrococcus horikoshii
3.4.22.B78 Zn2+ inhibits 64% at 0.2 mM, 77% at 1 mM, and precipitates the enzyme at 5 mM Pyrococcus horikoshii

KM Value [mM]

EC Number KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
3.4.22.B78 additional information
-
 additional information steady-state kinetics, recombinant wild-tyype and mutant enzymes, overview Pyrococcus horikoshii

Metals/Ions

EC Number Metals/Ions Comment Organism Structure
3.4.11.B7 Ca2+ 5 mM, 29% inhibition of protease activity Pyrococcus horikoshii
3.4.11.B7 Co2+ 0.2 mM, 75% inhibition of protease activity Pyrococcus horikoshii
3.4.11.B7 Cu2+ 0.2 mM, 57% inhibition of protease activity Pyrococcus horikoshii
3.4.11.B7 Fe3+ 0.2 mM, 27% inhibition of protease activity Pyrococcus horikoshii
3.4.11.B7 K+ 5 mM, 19% inhibition of protease activity Pyrococcus horikoshii
3.4.11.B7 Mg2+ 5 mM, 10% inhibition of protease activity Pyrococcus horikoshii
3.4.11.B7 Mn2+ 5 mM, 81% inhibition of protease activity Pyrococcus horikoshii
3.4.11.B7 Na+ 5 mM, 28% inhibition of protease activity Pyrococcus horikoshii
3.4.11.B7 Ni2+ 0.2 mM, 84% inhibition of protease activity Pyrococcus horikoshii
3.4.11.B7 Zn2+ 0.2 mM, 63% inhibition of protease activity Pyrococcus horikoshii
3.4.22.B78 Ca2+ 5 mM, 29% inhibition of protease activity Pyrococcus horikoshii
3.4.22.B78 Co2+ 0.2 mM, 75% inhibition of protease activity Pyrococcus horikoshii
3.4.22.B78 Cu2+ 0.2 mM, 57% inhibition of protease activity Pyrococcus horikoshii
3.4.22.B78 Fe3+ 0.2 mM, 27% inhibition of protease activity Pyrococcus horikoshii
3.4.22.B78 K+ 5 mM, 19% inhibition of protease activity Pyrococcus horikoshii
3.4.22.B78 Mg2+ 5 mM, 10% inhibition of protease activity Pyrococcus horikoshii
3.4.22.B78 Mn2+ 5 mM, 81% inhibition of protease activity Pyrococcus horikoshii
3.4.22.B78 Na+ 5 mM, 28% inhibition of protease activity Pyrococcus horikoshii
3.4.22.B78 Ni2+ 0.2 mM, 84% inhibition of protease activity Pyrococcus horikoshii
3.4.22.B78 Zn2+ 0.2 mM, 63% inhibition of protease activity Pyrococcus horikoshii

Molecular Weight [Da]

EC Number Molecular Weight [Da] Molecular Weight Maximum [Da] Comment Organism
3.4.11.B7 240000
-
 non-denaturing PAGE Pyrococcus horikoshii
3.4.22.B78 20000
-
 12 * 20000, about, recombinant enzyme, SDS-PAGE Pyrococcus horikoshii
3.4.22.B78 240000
-
 non-denaturing PAGE Pyrococcus horikoshii
3.4.22.B78 240000
-
 about, recombinant enzyme, native PAGE Pyrococcus horikoshii

Organism

EC Number Organism UniProt Comment Textmining
3.4.11.B7 Pyrococcus horikoshii O59413
-
-
3.4.11.B7 Pyrococcus horikoshii DSM 12428 O59413
-
-
3.4.22.B78 Pyrococcus horikoshii O59413
-
-
3.4.22.B78 Pyrococcus horikoshii DSM 12428 O59413
-
-
3.4.22.B78 Pyrococcus horikoshii OT-3 O59413
-
-

Purification (Commentary)

EC Number Purification (Comment) Organism
3.4.11.B7
-
 Pyrococcus horikoshii
3.4.22.B78
-
 Pyrococcus horikoshii
3.4.22.B78 recombinant wild-type and mutant enzymes from Escherichia coli strain BL21(DE3) by 8fold heat treatment at 80°C for 15 min, and gel filtration. Affinity chromatography is not suitable for this enzyme because recombinant PH1704 can be precipitated in the present of nickel Pyrococcus horikoshii

Reaction

EC Number Reaction Comment Organism Reaction ID
3.4.22.B78 the enzyme prefers substrates with an Arg residue at the P1 site it also acts as arginyl aminopeptidase with higher efficiency Pyrococcus horikoshii
a

Specific Activity [micromol/min/mg]

EC Number Specific Activity Minimum [µmol/min/mg] Specific Activity Maximum [µmol/min/mg] Comment Organism
3.4.22.B78 19.87
-
 purified recombinant wild-type enzyme, pH 7.5, 85°C Pyrococcus horikoshii

Substrates and Products (Substrate)

EC Number Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
3.4.11.B7 L-Ala-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amido-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii L-Ala + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Ala-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amido-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii DSM 12428 L-Ala + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Ala-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amido-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii OT-3 L-Ala + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Arg-7-amido-4-methylcoumarin + H2O the enzyme is also identified as an cysteine endopeptidase. Activity with the endopeptidase substrate Ala-Ala-Phe-Arg-7-amido-4-methylcoumarin is 10% compared to the activity with the aminopeptidase substrate L-Arg-7-amido-4-methylcoumarin. The enzyme exhibits primal aminopeptidase activity. The specific activity for hydrolyzing L-Arg-7-amido-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii L-Arg + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Arg-7-amido-4-methylcoumarin + H2O the enzyme is also identified as an cysteine endopeptidase. Activity with the endopeptidase substrate Ala-Ala-Phe-Arg-7-amido-4-methylcoumarin is 10% compared to the activity with the aminopeptidase substrate L-Arg-7-amido-4-methylcoumarin. The enzyme exhibits primal aminopeptidase activity. The specific activity for hydrolyzing L-Arg-7-amido-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii DSM 12428 L-Arg + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Arg-7-amido-4-methylcoumarin + H2O the enzyme is also identified as an cysteine endopeptidase. Activity with the endopeptidase substrate Ala-Ala-Phe-Arg-7-amido-4-methylcoumarin is 10% compared to the activity with the aminopeptidase substrate L-Arg-7-amido-4-methylcoumarin. The enzyme exhibits primal aminopeptidase activity. The specific activity for hydrolyzing L-Arg-7-amido-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii OT-3 L-Arg + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Asp-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amino-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amino-4-methylcoumarin, L-Ala-7-amino-4-methylcoumarin, L-Val-7-amino-4-methylcoumarin, L-Phe-7-amino-4-methylcoumarin or L-Ser-7-amino-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii L-Asp + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Asp-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amino-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amino-4-methylcoumarin, L-Ala-7-amino-4-methylcoumarin, L-Val-7-amino-4-methylcoumarin, L-Phe-7-amino-4-methylcoumarin or L-Ser-7-amino-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii DSM 12428 L-Asp + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Asp-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amino-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amino-4-methylcoumarin, L-Ala-7-amino-4-methylcoumarin, L-Val-7-amino-4-methylcoumarin, L-Phe-7-amino-4-methylcoumarin or L-Ser-7-amino-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii OT-3 L-Asp + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Phe-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amido-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii L-Phe + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Phe-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amido-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii DSM 12428 L-Phe + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Phe-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amido-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii OT-3 L-Phe + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Ser-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amino-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii L-Ser + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Ser-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amino-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii DSM 12428 L-Ser + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Ser-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amino-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii OT-3 L-Ser + 7-amino-4-methylcoumarin
-
 ?
3.4.11.B7 L-Val-7-amido-4-methylcoumarin + H2O the specific activity for hydrolyzing L-Arg-7-amido-4-methylcoumarin is 90times to 300times higher than those hydrolyzing L-Asp-7-amido-4-methylcoumarin, L-Ala-7-amido-4-methylcoumarin, L-Val-7-amido-4-methylcoumarin, L-Phe-7-amido-4-methylcoumarin or L-Ser-7-amido-4-methylcoumarin. Arginine, phenylalanine, alanine, valine, aspartate, and serine substrates are hydrolyzed with decreasing efficiency, in that order Pyrococcus horikoshii L-Val + 7-amino-4-methylcoumarin
-
 ?
3.4.22.B78 Ala-Ala-Leu-Arg-7-amido-4-methylcoumarin + H2O
-
 Pyrococcus horikoshii Ala-Ala-Leu-Arg + 7-amino-4-methylcoumarin
-
 ?
3.4.22.B78 Ala-Ala-Phe-7-amido-4-methylcoumarin + H2O
-
 Pyrococcus horikoshii Ala-Ala-Phe + 7-amino-4-methylcoumarin
-
 ?
3.4.22.B78 Ala-Ala-Phe-Arg-7-amido-4-methylcoumarin + H2O low activity Pyrococcus horikoshii Ala-Ala-Phe-Arg + 7-amino-4-methylcoumarin
-
 ?
3.4.22.B78 Ala-Ala-Phe-Arg-7-amido-4-methylcoumarin + H2O the enzyme is also identified as an aminopeptidase. Activity with the endopeptidase substrate Ala-Ala-Phe-Arg-7-amido-4-methylcoumarin is 10% compared to the activity with the aminopeptidase substrate L-Arg-7-amido-4-methylcoumarin Pyrococcus horikoshii Ala-Ala-Phe-Arg + 7-amino-4-methylcoumarin
-
 ?
3.4.22.B78 Ala-Arg-7-amido-4-methylcoumarin + H2O
-
 Pyrococcus horikoshii Ala-Arg + 7-amino-4-methylcoumarin
-
 ?
3.4.22.B78 Ala-Phe-7-amido-4-methylcoumarin + H2O
-
 Pyrococcus horikoshii Ala-Phe + 7-amino-4-methylcoumarin
-
 ?
3.4.22.B78 Gelatin + H2O
-
 Pyrococcus horikoshii ?
-
 ?
3.4.22.B78 Leu-Arg-7-amido-4-methylcoumarin + H2O
-
 Pyrococcus horikoshii Leu-Arg + 7-amino-4-methylcoumarin
-
 ?
3.4.22.B78 additional information the enzyme has both aminopeptidase and endopeptidase activities, substrate specificity, overview. Ala-Phe-7-amido-4-methylcoumarin, and Ala-Ala-Phe-7-amido-4-methylcoumarin are poor substrates. Phe-7-amido-4-methylcoumarin, Ala-7-amido-4-methylcoumarin, Val-7-amido-4-methylcoumarin, Asp-7-amido-4-methylcoumarin, and Ser-7-amido-4-methylcoumarin are no substrates Pyrococcus horikoshii ?
-
 ?

Subunits

EC Number Subunits Comment Organism
3.4.11.B7 dodecamer
-
 Pyrococcus horikoshii
3.4.22.B78 dodecamer
-
 Pyrococcus horikoshii
3.4.22.B78 dodecamer 12 * 20000, about, recombinant enzyme, SDS-PAGE Pyrococcus horikoshii

Synonyms

EC Number Synonyms Comment Organism
3.4.11.B7 arginine-specific aminopeptidase
-
 Pyrococcus horikoshii
3.4.11.B7 PH1704 protease ambiguous, the recombinant protein is also identified as a cysteine endopeptidase Pyrococcus horikoshii
3.4.22.B78 PH1704
-
 Pyrococcus horikoshii
3.4.22.B78 PH1704 protease
-
 Pyrococcus horikoshii
3.4.22.B78 PH1704 protease ambiguous, the recombinant protein is also identified as an aminopeptidase Pyrococcus horikoshii

Temperature Optimum [°C]

EC Number Temperature Optimum [°C] Temperature Optimum Maximum [°C] Comment Organism
3.4.22.B78 80
-
-
 Pyrococcus horikoshii
3.4.22.B78 85
-
 assay at Pyrococcus horikoshii

Temperature Range [°C]

EC Number Temperature Minimum [°C] Temperature Maximum [°C] Comment Organism
3.4.22.B78 50 95 50°C: about 60% of maximal activity, 95°C: about 60% of maximal activity Pyrococcus horikoshii

pH Optimum

EC Number pH Optimum Minimum pH Optimum Maximum Comment Organism
3.4.22.B78 7.5
-
 assay at Pyrococcus horikoshii
3.4.22.B78 8.5
-
-
 Pyrococcus horikoshii

pH Range

EC Number pH Minimum pH Maximum Comment Organism
3.4.22.B78 6.5 9 pH 6.5: about 45% of maximal activity, pH 9.0: about 55% of maximal activity Pyrococcus horikoshii

General Information

EC Number General Information Comment Organism
3.4.22.B78 evolution the enzyme is a member of DJ-1/ThiJ/PfpI superfamily that has diverse functional subclasses Pyrococcus horikoshii
3.4.22.B78 additional information the enzyme has both aminopeptidase and endopeptidase activities, Cys100 is the catalytic nucleophilic residue, residue Tyr120 is important in substrate binding and is involved in enzyme activity to form a hydrogen bond with Cys100 and as an entrance gate of the substrate with Lys43, active site pocket structure, molecular docking study, overview. Cys100, His101, and Glu474 function as a catalytic triad. Active residues are Glu12, Glu15, Lys43, Gly70, Arg71, Cys100, His101, Tyr120, Val150, Arg471, Glu474, and Arg475 Pyrococcus horikoshii