ENZYMES, GROWTH FACTORS, PROTEINS, AND RECEPTORS

Penicillin-Binding Protein (PBP)

A serine protease/transpeptidase that allows the attachment of polypeptide cross-links between polysaccharide backbones

Serine protease/transpeptidase

The function of Penicillin-Binding Protein (PBP)

Renal dehydropeptidase

The enzyme inhibited by cilastatin

Alanine racemase

The enzyme that converts L-Alanine to D-Alanine

D-alanyl-D-alanine ligase

The enzyme that attaches one D-Alanine to another D-Alanine to form a dimer

Enolpyruvate transferase

The enzyme that naturally occurs more in the cytoplasm and is targeted by fosfomycin

LytA

An autolysin which actively breaks down cell walls

Enterobacteria esterases

The enzyme that destroys the macrocyclic lactone ring

Methylase

The enzyme that modifies the macrolide target, preventing the drug from binding

Cytochrome P450 (CYP450) enzyme inhibitors

Drugs that inhibit this enzyme, thereby slowing the metabolism and excretion of drugs and increasing drug circulation time

Fungal cytochrome P450 enzyme lanosterol 14 alpha-demethylase (c-14 alpha-demethylase)

The enzyme that is blocked by azoles to inhibit the conversion of lanosterol to ergosterol

Human gonadal and adrenal steroid synthesis

The biological process inhibited by ketoconazole, leading to decreased testosterone and cortisol production

Ribosomal protection

A mechanism of bacterial resistance to tetracyclines that Tigecycline can overcome

Efflux pumps

The mechanism bacteria use to "vomit out" drugs like tetracycline or ciprofloxacin, expelling them from the cell

Topoisomerase II (DNA gyrase)

The enzyme targeted by fluoroquinolones in gram-negative organisms to relax supercoiled DNA and promote DNA strand breakage

Topoisomerase IV

The enzyme targeted by fluoroquinolones in gram-positive organisms that stabilizes chromosomes during cell division and interferes with the separation of newly replicated DNA

Cytosine permease

The fungal enzyme that allows 5-FC to enter the cell and is absent in mammalian cells

Cytosine deaminase

The enzyme that converts 5-FC to 5-fluorouracil (5-FU) and is absent in mammalian cells

Uridine phosphoribosyl transferase

The enzyme that converts 5-FU to 5-fluorouridine monophosphate (5-FUMP)

Ribonucleotide reductase

The enzyme involved in converting 5-FUMP to 5-fluorodeoxyuridine monophosphate (5-FdUMP)

Thymidylate synthase

The enzyme inhibited by 5-fluorodeoxyuridine monophosphate (5-FdUMP)

5-fluorodeoxyuridine monophosphate (5-FdUMP)

A false nucleotide derivative of 5-FC that inhibits thymidylate synthase

5-fluorouridine triphosphate (5-FUTP)

The compound incorporated into RNA that creates a faulty strand and interferes with RNA synthesis

Dihydropteroate synthetase (or synthase)

The enzyme inhibited by sulfonamides in bacteria that synthesizes dihydrofolic acid from PABA, pteridine, and glutamate

Dihydrofolate reductase

The enzyme that converts dihydrofolic acid to tetrahydrofolic acid and is potently inhibited by trimethoprim

Elongation factor EF-G

The specific factor inhibited by fusidic acid

Beta-(1-3)-D-glucan synthesis

The synthesis process essential to the cell wall integrity of many fungi, which is inhibited by caspofungin

Squalene epoxidase

The enzyme inhibited by terbinafine/naftifine, blocking the conversion of squalene to lanosterol

Tubulins (microtubules)

The structures in fungi that griseofulvin binds to, disrupting mitotic spindle formation

P-glycoprotein mediated transporters

The transporters activated by penicillin to increase the uptake of aminoglycosides

30s ribosomal unit

The smaller subunit of the bacterial ribosome targeted by aminoglycosides and tetracyclines

50s ribosomal unit

The larger subunit of the bacterial ribosome targeted by macrolides, chloramphenicol, and others

70s rRNA

The ribosomal structure characteristic of bacterial and mitochondrial ribosomal RNA

80s rRNA

The ribosomal structure characteristic of cytosolic ribosomal RNA

23s subunit of 50s rRNA subunit

The specific site where oxazolidinones bind to block ribosome assembly

Aminoacyl tRNA

The molecule whose binding to the A-site is blocked by tetracyclines

Translocation

The process of aminoacyl tRNA movement from the A-site that is blocked by macrolides and similar drugs

K+ efflux

The process caused by daptomycin binding to the bacterial membrane, leading to rapid depolarization

Bactoprenol (undecaprenol pyrophosphate, C55-PP)

The molecule responsible for shuttling peptidoglycan subunits from the cytosol to the cell wall

MurNac synthesis

The synthesis process blocked when the attachment of phosphoenolpyruvate to GlcNaC is inhibited by fosfomycin

Dihydrofolate synthetase

The enzyme that catalyzes the conversion from dihydropteroic acid into dihydrofolic acid, according to some illustrations

DNA-directed RNA polymerase

The enzyme targeted by rifampin/rifampicin to inhibit RNA synthesis

p-Aminobenzoic acid (PABA)

The constituent of folic acid synthesized by bacteria that sulfonamides structurally resemble

Dihydrofolic acid

The compound synthesized from PABA, pteridine, and glutamate, whose conversion to tetrahydrofolic acid is blocked by trimethoprim

Tetrahydrofolic acid

The critical folate derivative needed for purine and pyrimidine synthesis

Glucuronidation

The process in the liver by which chloramphenicol is inactivated

Cytochrome P450 (CYP450)

The human enzyme whose inhibition by azoles increases the toxicity of other drugs

Steroid/Testosterone synthesis

The synthesis process inhibited by ketoconazole, leading to effects such as gynecomastia and menstrual irregularities

Monoamine oxidase inhibitor (MAO)

The functional characteristic of linezolid that results in sympathomimetic effects and synergy with psychiatric drugs

Keratin

The protein-containing tissue in newly formed skin and nails where griseofulvin is deposited

D-Ala-D-Ala terminus of the peptidoglycan pentapeptide side chain

The target where vancomycin binds with H-bonds to prevent further peptidoglycan elongation

Penicillin-Binding Protein (PBP)

The target of beta-lactam compounds

Bactoprenol

The molecule targeted by bacitracin

Alanine racemase & D-alanyl-D-alanine ligase

The two enzymes targeted by cycloserine

Enolpyruvate transferase

The enzyme targeted by fosfomycin

Peptidoglycan (Murein)

The cell wall component that is more prevalent in Gram positive bacteria

Lipopolysaccharides (LPS)

The toxic virulence factors attached to the outer membrane of Gram negative bacteria

Lipoteichoic acid

The molecule that anchors the thicker peptidoglycan layer of Gram positive bacteria to the cell membrane

Mycolic acids

The long chains in the cell wall that define Mycobacteria

Chitin

The glycopeptide found in the cell wall of Fungi

Ergosterol

The principal sterol of fungal cell membranes

Cholesterol

The human sterol that amphotericin B binds to, causing adverse effects

Lanosterol

The molecule that is demethylated by 14 alpha-demethylase to form ergosterol

Squalene

The molecule whose accumulation leads to decreased cell membrane permeability and fungal death when squalene epoxidase is inhibited

D-Ala-D-Ala terminus

The moiety whose formation in the peptidoglycan is inhibited by cycloserine

GlcNaC

The molecule whose attachment to phosphoenolpyruvate is blocked by fosfomycin

Phosphoenolpyruvate

The precursor in peptidoglycan cell wall construction that fosfomycin is a structural analog of

Folic acid (FA)

The compound needed for the synthesis of pyrimidines and purines

Dihydropteroic acid

The compound that conjugates with glutamic acid to form dihydrofolic acid

Purine and pyrimidine synthesis

The processes requiring tetrahydrofolic acid cofactors for DNA and RNA precursor production

D-Alanine dimer

The molecule whose formation is prevented by the ligase effect of cycloserine

Albumin

The bilirubin binding sites displaced by sulfonamides

Cationic Antimicrobial Peptide and EDTA

Two examples of permeabilizers that soften the bacterial cell wall

Capsaicin

An example of a molecule that inhibits efflux pumps

Savirin

An example of a quorum sensing inhibitor

Urtoxazumab

An antibody specific to bacterial toxins

Coil A and Coil B

Two molecules that inhibit the type three secretion system, preventing the expulsion of contents

Post antibiotic Leukocyte Enhancement (PALE)

The phenomenon where enhanced leukocyte function makes organisms more susceptible to antibacterial activity after antibiotic exposure

Dihydropteroic acid

The compound that is formed through the competitive inhibition of PABA by sulfonamides

Lanosterol 14 alpha-demethylase

The enzyme that blocks the demethylation of lanosterol to ergosterol

5-fluorouracil (5-FU)

The toxic antineoplastic metabolite of flucytosine responsible for hematologic disturbances

23s RNA of 50s

The specific site targeted by Linezolid on the ribosomal subunit

Peptidoglycan subunits

The structural units blocked from crossing the cell membrane by inhibiting the dephosphorylation of Bactoprenol

Virulence factors

The factors contained within the bacterial cell wall that enhance adhesion to living tissue

Biofilm

A bacterial ecosystem that fosters cell maturity and virulence factor expression

Resistance enzymes

The enzymes whose de-repression is a mechanism of drug antagonism

Endotoxin or exotoxin

Two molecules that represent the microbial mechanism of damage

Tetrahydrofolate (THF)

The molecule produced after the third step in the bacterial folic acid pathway, targeted by trimethoprim

Dihydrofolate (DHF)

The molecule produced after the first step in the bacterial folic acid pathway, targeted by sulfonamides

Purine and Pyrimidine synthesis

The processes required by bacteria for DNA and RNA precursors

Reactive Oxygen Species (ROS)

The molecules produced by metronidazole and nitrofurantoin that affect DNA integrity

Dihydropteroate synthetase

The enzyme that catalyzes the conversion of PABA to Dihydrofolate (DHF)

Dihydrofolate reductase

The enzyme that catalyzes the conversion of Dihydrofolate (DHF) to Tetrahydrofolate (THF)

Alpha-demethylase

The enzyme whose inhibition prevents the conversion of lanosterol to ergosterol

Dephosphorylation of Bactoprenol

The process inhibited by Bacitracin, preventing building blocks from crossing the cell membrane

Beta-lactamases

The enzymes produced by bacteria that destroy the beta-lactam ring of the penicillin backbone

Beta-lactam ring

The crucial structural component of penicillin that is destroyed by beta-lactamases

6-aminopenicillanic acid

The common backbone or nucleus of penicillins

7-aminocephalosporanic acid

The common nucleus and backbone of cephalosporins

Hapten

A small molecule that, when bound to a larger molecule like a protein carrier, can trigger an antibody response