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The Claim

The eNTRy rules, developed by Richer et al. in 2017, identify specific physicochemical properties—ionizable nitrogen (especially a primary amine), low three dimensionality, and rigidity—that increase the likelihood of compound accumulation in Escherichia coli, thereby improving the potential for antibiotic activity against Gram-negative bacteria.

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The Short Version

The claim accurately captures the core eNTRy rules—ionizable nitrogen, low three-dimensionality, and rigidity—as properties that increase compound accumulation in E. coli and improve Gram-negative antibiotic potential, as established by Richer et al. in 2017. Two minor caveats apply: the original ionizable nitrogen criterion is broader than primary amines alone (secondary amines also qualify), and the foundational paper additionally highlighted amphiphilicity as part of the accumulator profile, which the claim omits. These do not change the practical takeaway but slightly over-narrow the actual rules.

Caveats

  • The eNTRy 'ionizable nitrogen' criterion is broader than primary amines; secondary amines and other ionizable nitrogens can also satisfy the rule, so the claim's 'especially a primary amine' emphasis is somewhat over-specific.
  • Richer et al. (2017) also identified amphiphilicity as part of the accumulator profile, which the claim omits entirely.
  • These physicochemical properties increase the probability of accumulation but do not guarantee it; efflux mechanisms and other factors mean many amine-containing compounds still fail to accumulate in Gram-negative bacteria.

The Receipts

  1. Predictive rules for compound accumulation yield a broad-spectrum antibiotic

    PMC

  2. Facilitating Compound Entry as a Means to Discover Antibiotics for Gram-Negative Pathogens

    PubMed Central (NIH)

  3. Predictive compound accumulation rules yield a broad-spectrum antibiotic - PubMed

    PubMed

  4. Predictive rules for compound accumulation yield a broad-spectrum antibiotic - PMC

    PMC

  5. Breaching the Barrier: Genome-Wide Investigation into the Role of a Primary Amine in Promoting E. coli Outer-Membrane Passage and Growth Inhibition by Ampicillin - PubMed

    PubMed

  6. Physicochemical and Structural Parameters Contributing to the Antibacterial Activity and Efflux Susceptibility of Small-Molecule Inhibitors of Escherichia coli - PMC

    PMC

  7. Permeability barriers of Gram-negative pathogens - PMC - NIH

    PMC

  8. Defining New Chemical Space for Drug Penetration into Gram-Negative Bacteria

    PubMed Central (NIH)

  9. New rules for cellular entry may aid antibiotic development - Science News

    Science News

  10. eNTRy rules

    GARDP Revive (Global Antibiotic Research and Development Partnership)

+ 5 more sources — see the full list on Lenz

Filed Under

eNTRy rulesEscherichia coliRicher et al.

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