The document discusses various types of supramolecular complexes formed through self-assembly of macromolecules. It describes the plasma membrane as composed of lipids, proteins, and carbohydrates that form a bilayer through hydrophobic interactions. Ribosomes are composed of RNA and proteins that bind independently and come together to form the small and large subunits. Nucleosomes consist of DNA wrapped around histone proteins to compact DNA into beads with repeating units that further coil to form chromatin.

1. Supramolecules assembly
By
KAUSHAL KUMAR SAHU
Assistant Professor (Ad Hoc)
Department of Biotechnology
Govt. Digvijay Autonomous P. G. College
Raj-Nandgaon ( C. G. )

2. Synopsis
• Introduction
• Types of supramolecules complexes
 Plasma membrane
 Ribosome
 Nucleosomes
• Conclusion
• References

3. Introduction
Supramolecules complex is well defined complex of
molecules held together by non covalent bonds.
The assembly of the macromolecules in an ordered manner
to create higher order supramolecule structure is called
supramolecules assembly.
Also called molecules self assembly.
The dimensions of supramolecular assemblies can range
from nanometers to micrometers.

4. • Macromolecules are
 Polysaccharide
 Polynucleotide
 Proteins
 Lipids
• Non covalent bonds
 Ionic bond
 Hydrogen bond
 Hydrophobic bond
 Vander Waal bond
• Supramolecules complexes
 Plasma membrane
 Ribosomes
 Nucleosomes
 Cell wall

5. Plasma membrane
• Plasma membrane is composed of
 Proteins
 Lipids
 Carbohydrates

6. Lipid Bilayer
• Glycerophospholipids, sphingolipids, & sterols are
insoluble in water, so when they mixed with water
they spontaneously form microscopic lipid
aggregates with their moieties in contact with each
other and their hydrophilic groups interacting with
surrounding water.
• 3 types of lipid aggregates-
 Micelles
 Bilayer
 Vesicles
• Lipids are asymmetrically distributed between th e
two monolayer of the bilayer.

7. • Example- PM of erythrocytes-
choline containing lipid- outer leaflet
Phosphatidylserine, phosphatidylethanolamine,
phosphatidylinositol –inner leaflet.

8. Proteins
3 types….
• Integral membrane protein
Firmly associated with lipid bilayer with hydrophobic
interaction.
• Peripheral membrane proteins
associate with membrane through ionic bonds and
hydrogen bonding with the hydrophilic domains of integral
proteins and with the polar head groups of membrane
lipid.
• Amphitropic proteins
the protein's non covalent interaction with a membrane
protein or lipid,
reversible association

9. Interaction between lipid, proteins &
carbohydrates
• Hydrophobic interactions between membrane lipids and
hydrophobic domains of the protein.
• α helix type protein mostly found.
• β barrel found in bacterial membrane.
• Both the amino and carboxyl terminus contains many polar or
charged amino acids residue and are therefore hydrophilic.
• Segment in the center of protein contains hydrophobic, non
polar amino acid residues.
• Phospholipids molecules lie on the protein surface, their head
groups interacting with the polar amino acids residues at the
inner and outer membrane- water interfaces and their side
chains associated with the non polar residues. These annular
lipids form a bilayer shell around the protein.
• Tyr and Trp residue – membrane interface anchors.
• Lys, His, Arg- positively charged – present on cytoplasmic
membrane

11. Cont…
• Membrane proteins contain one or more covalently linked
lipids – like long chain fatty acid, isoprenoids, and sterols.
• Other interactions are ionic attraction between positively
charged Lys residue in the protein and negatively charged
lipid head groups contribute the stability.
• Plasma membrane glycoproteins are always oriented with
the oligosaccharide bearing domain on the extracellular
surface.

12. Ribosomes
Prokaryotes
70s
50s
31
POLYNUCLE
OTIDE
5S rRNA
23s rRNA
30s
21
POLYNUCLE
OTIDES
16s rRNA
EUKARYOTES
80S
40S
18S rRNA
33
POLYNUCLEOT
IDES
60S
28S
5.8S
5S
49
POLYNUCLE
OTIDES

13. Self assembling of Ribosomes
• Nomura constructed an assembly
map of the small (30S) subunit (Fig.
32-29). This map indicates that the
initial steps in small subunit assembly
are the independent binding to naked
16S rRNA of six so-called primary
(1°) binding proteins (S4, S7, S8, S15,
S17, and S20).
• The resulting assembly intermediates
provide the molecular scaffolding for
binding secondary (2°) binding
proteins, which after a significant
conformational change; form the
attachment sites for tertiary (3°)
binding proteins.
• K. Nierhaus proposed assembly map
of large subunit.

14. Ribosomal Architecture
• Both the 16S and 23S rRNAs are assemblies of coaxially stacked
helical elements connected by loops, stabilized by interactions
between helices such as minor groove to minor groove packing,
phosphate ridge and adenines inserted in minor grooves.
• 16S RNA’s four domains, forms a morphologically distinct
portion of the 30S subunit:
 The 5’ domain -body;
 the central domain -platform,
 the 3’ major domain -entire head, and
 the 3’ minor domain - located at the interface between the 30S
and 50S subunits.
• In contrast, the 23S RNA’s six domains are intricately
intertwined in the 50S subunit.
• majority of the ribosomal proteins are located on the back
and sides of their subunits.
• the face of each subunit that forms the interface between the two
subunits, particularly those regions that bind the tRNAs and
mRNA, is largely devoid of proteins

15. Cont…
• Ribosomal proteins consist of
 a globular domain-located on
a subunit surface
 a long segment - infiltrates
between the RNA helices into
the subunit interior.
• They tend to interact with the
RNA through salt bridges
between their positively
charged side chains and the
RNAs’ negatively charged
phosphate oxygen atoms,
thereby neutralizing the
repulsive charge–charge
interactions between nearby
RNA segments.
• The small and large
ribosomal subunits contact
each other at 12 positions via
RNA–RNA, protein–protein,
and RNA–protein bridges

16. Nucleosomes
• structure in which the DNA is
bound tightly to beads of protein
• The bead of each nucleosome
contains eight histone molecules:
two copies each of H2A, H2B, H3,
and H4.
• The spacing of the nucleosome
beads provides repeating units
typically of about 200 bp, of
which 146 bp are bound tightly
around the eight- part histone
core and the remainder serve as
linker DNA between nucleosome
beads.
• Histone H1 binds to the linker
DNA.
• Local abundance of A=T pairs in
the DNA helix where it is in contact
with the histones, facilitating the
compression of the minor groove
that is needed for the tight
wrapping of the DNA around
nucleosome’s histone core.

17. Folding of Nucleosome
• Nucleosomes are deposited on the DNA during
replication in a stepwise manner.
• A tetramer of two H3 and two H4 histones binds
first followed by deposition of H2A- H2B
dimers.
• Wrapping of DNA around a nucleosome core
compacts the DNA length about sevenfold.
• Nucleosome cores seem to be organized into a
structure called the 30 nm fiber.
• This packing requires one molecule of histone
H1 per nucleosome core. Organization into
30nm fibers does not extend over the entire
chromosome but is punctuated by regions
bound by sequence- specific (nonhistone) DNA-
binding proteins.
• The 30 nm fiber (a second level of chromatin
organization) provides an approximately 100
fold compaction of the DNA. T he higher-order
folding involves attachment to a nuclear
scaffold that contains histone Hl, topoisomerase
II, and SMC proteins.
• Large amount of H1 located in the interior of
fibers.

18. Conclusion
• Macromolecules like proteins, lipids,
carbohydrates, DNA and RNA are held
together by non covalent bonds like
hydrophobic bonds, hydrogen bonds, ionic
bond to form a well organized complex
called the supramolecules complexes like
plasma membrane, ribosomes, nucleosomes
etc.

19. References
• Lehninger Principle of Biochemistry – 5th
edition – David L. Nelson and Michael M.
Cox.
• Biochemistry – Voet and Voet – 4th edition.