black pigmented

Edge evidence

• phenolic precursors feed into melanin biosynthesis

  Phenolic precursors feed oxidative melanin-forming pathways.

  • DOI:10.1007/s11274-020-02941-z oxidative polymerization of tyrosine derivatives Supports phenolic or tyrosine-derived precursors as melanin biosynthetic substrates.
• tyrosinase/laccase oxidases catalyzes melanin biosynthesis biolink:catalyzes

  Oxidases catalyze precursor oxidation in melanin formation.

  • DOI:10.1016/j.biotechadv.2021.107773 biosynthesis ... oxidative polymerization Supports oxidative enzymatic routes for microbial melanin formation.
• melanin biosynthesis produces black-brown melanin METPO:2000202

  Melanin biosynthesis produces dark melanin polymers.

  • DOI:10.1016/j.biotechadv.2021.107773 Eumelanin and allomelanin impart black/brown color Supports black-brown melanins as microbial colorants.
• black-brown melanin causes visible black color biolink:causes

  Dark melanin polymers cause visible black pigmentation when sufficiently accumulated.

  • DOI:10.1016/j.biotechadv.2021.107773 black/brown color Supports black color as an outcome of dark melanin accumulation.
• visible black color manifests as black pigmented METPO:2007400

  Visible black color manifests the black-pigmented phenotype.

  • DOI:10.1016/j.biotechadv.2021.107773 black/brown color to the cells Supports the trait-level assignment.
• tyrosinase catalyzes conversion of L-tyrosine

  Tyrosinase hydroxylates L-tyrosine to L-DOPA, initiating the DOPA-melanin pathway.

  • DOI:10.3390/ijms25053013 Tyrosinase first catalyzes the hydroxylation of L-tyrosine to L-DOPA.
• dopaquinone/dihydroxyindole intermediates polymerizes into DOPA-melanin (eumelanin)

  Dopaquinone/dihydroxyindole intermediates polymerize into DOPA-melanin (eumelanin).

  • DOI:10.3390/jof9090891 Dopaquinone oxidized to dopachrome then dihydroxy-indoles which polymerize to form DOPA-melanins.
• copper ion required cofactor for tyrosinase

  Copper ions are required cofactors for tyrosinase catalytic activity.

  • DOI:10.3390/microorganisms12071352 Tyrosinases are copper-dependent enzymes.
• polyketide synthase (PKS) synthesizes precursor for DHN (1,8-dihydroxynaphthalene)

  Polyketide synthase forms tetrahydroxynaphthalene leading to DHN, precursor of DHN-melanin.

  • DOI:10.3390/microorganisms12071352 Polyketide synthase forms 1,3,6,8-tetrahydroxynaphthalene; polymerization of DHN leads to melanin.
• DHN (1,8-dihydroxynaphthalene) polymerizes into DHN-melanin (allomelanin)

  DHN polymerizes into DHN-melanin (allomelanin), a dark pigment.

  • DOI:10.3390/microorganisms12071352 Polymerization of DHN leads to the formation of melanin.
• HppD (4-hydroxyphenylpyruvate dioxygenase) converts 4-hydroxyphenylpyruvate

  HppD converts 4-hydroxyphenylpyruvate to homogentisic acid in the pyomelanin pathway.

  • DOI:10.1128/spectrum.00410-24 hppD codes for a protein responsible for conversion of 4-hydroxyphenylpyruvate to HGA.
• HmgA (homogentisate 1,2-dioxygenase) converts homogentisic acid (HGA)

  HmgA (homogentisate 1,2-dioxygenase) converts HGA to maleylacetoacetate.

  • DOI:10.1128/spectrum.00410-24 Homogentisate 1,2-dioxygenase encoded by hmgA converts HGA to maleylacetoacetate.