Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4¶
Why this mattered¶
Laemmli’s paper mattered far beyond its immediate subject, bacteriophage T4 head assembly, because it made protein composition experimentally legible at a new level of resolution. The paper showed that specific structural proteins of the phage head were cleaved during assembly, so viral morphogenesis could be understood not merely as aggregation of preformed parts but as an ordered biochemical process involving proteolytic processing. That shifted attention from static “parts lists” of virions toward assembly pathways, precursor-product relationships, and regulated maturation steps.
Its larger paradigm shift came from the method embedded in the work: SDS-polyacrylamide gel electrophoresis in the Laemmli system. By denaturing proteins with SDS and separating them reproducibly by apparent molecular weight, the paper gave biologists a practical way to compare complex protein mixtures as banding patterns. After this, identifying protein subunits, following processing events, checking purification fractions, and estimating molecular weights became routine rather than specialized feats.
That technical standard helped enable much of modern molecular biology and biochemistry: viral assembly studies, membrane-protein work, enzyme purification, immunoblotting, recombinant protein validation, and later proteomics all relied on the ability to resolve proteins cleanly and reproducibly. The paper’s extraordinary citation count reflects this dual legacy: it advanced a concrete model of bacteriophage morphogenesis while also giving laboratories a general-purpose protein-separation platform that became one of the basic measurement tools of the molecular life sciences.
Abstract¶
(no abstract available)
Related¶
- cite → The Reliability of Molecular Weight Determinations by Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis — The bacteriophage T4 protein-cleavage paper relies on SDS-polyacrylamide gel electrophoresis to estimate molecular weights of viral structural proteins.
- cite → DISC ELECTROPHORESIS – II METHOD AND APPLICATION TO HUMAN SERUM PROTEINS* — The bacteriophage T4 paper builds on disc electrophoresis methodology for separating proteins during analysis of phage head assembly.
- enables → High resolution two-dimensional electrophoresis of proteins. — SDS-polyacrylamide gel electrophoresis from the bacteriophage T4 protein study provided the molecular-weight separation dimension used in two-dimensional protein electrophoresis.
- enables → Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. — Laemmli's SDS-PAGE protein separation method created the gel-based protein bands that Towbin et al. transferred to nitrocellulose in Western blotting.
- cite ← High resolution two-dimensional electrophoresis of proteins. — O'Farrell cites Laemmli's SDS-PAGE protein separation method as a core electrophoretic component of two-dimensional protein analysis.
- cite ← Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. — The protein-transfer method relies on SDS-polyacrylamide gel electrophoresis popularized in Laemmli's bacteriophage T4 protein-separation work.
- enables ← DISC ELECTROPHORESIS – II METHOD AND APPLICATION TO HUMAN SERUM PROTEINS* — Disc electrophoresis supplied the gel-separation method that Laemmli adapted into SDS-PAGE for resolving bacteriophage T4 structural proteins.
Sources¶
- DOI: https://doi.org/10.1038/227680a0
- OpenAlex: https://openalex.org/W2100837269