Methods for the identification of inhibitors of putrescine aminopropyltransferase as antibiotics

A method for identifying a test compound as a candidate for an antibiotic, comprising:

• a) contacting a test compound with at least one polypeptide selected from the group consisting of:
• a polypeptide having at least ten consecutive amino acids of a fungal Putrescine Aminopropyltransferase, a polypeptide having at least 50% sequence identity with a fungal Putrescine Aminopropyltransferase, and a polypeptide having at least 10% of the activity thereof;
• and
• b) detecting the presence and/or absence of binding between said test compound and said polypeptide, wherein binding indicates that said test compound is a candidate for an antibiotic.

A method for identifying a test compound as a candidate for an antibiotic, comprising:

• a) contacting S-adenosylmethioninamine and putrescine with a Putrescine Aminopropyltransferase;
• b) contacting S-adenosylmethioninamine and putrescine with Putrescine Aminopropyltransferase and a test compound;
• and
• c) determining the change in concentration for at least one of the following:
• S-adenosylmethioninamine, putrescine, 5′-Methylthioadenosine, and/or Spermidine, wherein a change in concentration for any of the above substances between steps (a) and (b) indicates that said test compound is a candidate for an antibiotic.

A method for identifying a test compound as a candidate for an antibiotic, comprising:

• a) contacting 5′-methylthioadenosine and spermidine with a Putrescine Aminopropyltransferase;
• b) contacting 5′-methylthioadenosine and spermidine with a Putrescine Aminopropyltransferase and a test compound;
• and
• c) determining the change in concentration for at least one of the following:
• S-adenosylmethioninamine, putrescine, 5′-Methylthioadenosine, and/or Spermidine, wherein a change in concentration for any of the above substances between steps (a) and (b) indicates that said test compound is a candidate for an antibiotic.

A method for identifying a test compound as a candidate for an antibiotic, comprising:

• a) contacting S-adenosylmethioninamine and putrescine with a polypeptide selected from the group consisting of:
• a polypeptide having at least 50% sequence identity with Putrescine Aminopropyltransferase, a polypeptide having at least 50% sequence identity with a Putrescine Aminopropyltransferase and having at least 10% of the activity thereof, and a polypeptide comprising at least 100 consecutive amino acids of a Putrescine Aminopropyltransferase;
• b) contacting S-adenosylmethioninamine and putrescine with said polypeptide and a test compound;
• and
• c) determining the change in concentration for at least one of the following:
• S-adenosylmethioninamine, putrescine, 5′-Methylthioadenosine, and/or Spermidine, wherein a change in concentration for any of the above substances between steps (a) and (b) indicates that said test compound is a candidate for an antibiotic.

A method for identifying a test compound as a candidate for an antibiotic, comprising:

• a) contacting 5′-methylthioadenosine and spermidine with a polypeptide selected from the group consisting of:
• a polypeptide having at least 50% sequence identity with a Putrescine Aminopropyltransferase, a polypeptide having at least 50% sequence identity with a Putrescine Aminopropyltransferase and at least 10% of the activity thereof, and a polypeptide comprising at least 100 consecutive amino acids of a Putrescine Aminopropyltransferase;
• b) contacting 5′-methylthioadenosine and spermidine, with said polypeptide and a test compound;
• and
• c) determining the change in concentration for at least one of the following:
• S-adenosylmethioninamine, putrescine, 5′-Methylthioadenosine, and/or Spermidine, wherein a change in concentration for any of the above substances between steps (a) and (b) indicates that said test compound is a candidate for an antibiotic.

A method for identifying a test compound as a candidate for an antibiotic, comprising:

• a) measuring the expression of a Putrescine Aminopropyltransferase in a cell, cells, tissue, or an organism in the absence of a test compound;
• b) contacting said cell, cells, tissue, or organism with said test compound and measuring the expression of said Putrescine Aminopropyltransferase in said cell, cells, tissue, or organism;
• and
• c) comparing the expression of Putrescine Aminopropyltransferase in steps (a) and (b), wherein a lower expression in the presence of said test compound indicates that said test compound is a candidate for an antibiotic.

A method for identifying a test compound as a candidate for an antibiotic, comprising:

• a) providing cells having one form of a gene in the polyamine biochemical and/or genetic pathway and providing comparison cells having a different form of said gene;
• b) contacting said cells and said comparison cells with a said test compound;
• and
• c) determining the growth of said cells and said comparison cells in the presence of said test compound, wherein a difference in growth between said cells and said comparison cells in the presence of said test compound indicates that said test compound is a candidate for an antibiotic.

A method for identifying a test compound as a candidate for an antibiotic, comprising:

• (a) providing paired growth media comprising a first medium and a second medium, wherein said second medium contains a higher level of a polyamine than said first medium;
• (b) contacting an organism with a test compound;
• (c) inoculating said first and said second media with said organism;
• and
• (d) determining the growth of said organism, wherein a difference in growth of the organism between said first and said second media indicates that said test compound is a candidate for an antibiotic.