Biomolecular complex

Biomolecular complex, also called macromolecular complex or biomacromolecular complex, is any biological complex made of more than one molecule of protein, RNA, DNA,

lipids, or carbohydrates. The interactions between these biomolecules are non-covalent.

Examples:
 Protein complexes, some of which are multienzyme complexes: proteasome, DNA polymerase III holoenzyme, RNA polymerase II holoenzyme, symmetric viral capsids, chaperonin complex GroEL-GroES, photosystem I, ATP synthase, ferritin.
 RNA-protein complexes: ribosome, spliceosome, vault, SnRNP. Such complexes in cell nucleus are called ribonucleoproteins (RNPs).
 DNA-protein complexes: nucleosome.
 Protein-lipid complexes: lipoprotein.

The biomacromolecular complexes are studied structurally by X-ray crystallography, NMR spectroscopy of proteins, cryo-electron microscopy and successive single particle analysis, and electron tomography.

The atomic structure models obtained by X-ray crystallography and biomolecular NMR spectroscopy can be docked into the much larger structures of biomolecular complexes obtained by lower resolution techniques like electron microscopy, electron tomography, and small-angle X-ray scattering.

See also
 Quaternary structure
 Multiprotein complex
 Macromolecular assembly: macromolecular assembly in biology is the same as biomacromolecular complex.
 Organelle: the broadest definition of "organelle" includes not only membrane bound cellular structures, but also very large biomolecular complexes.
 Multi-state modeling of biomolecules

References

Further reading
   and , Biochemistry. (W. H. Freeman and Company, 2002), 
  and , Lehninger Principles of Biochemistry. (Palgrave Macmillan, 2004), 

 

Category:Protein complexes
Category:RNA
Category:Structural biology
Category:Molecular biology
Category:Cell biology