Composition of bacteria

Composition of bacteria
Following are some structures found in the composition of bacteria.

Capsule

               An outermost layer that surround the cell wall

Cell wall

                A layer that is made up of peptidoglycan

Cytoplasm

                    Aqueous part containing most of plasmid, nucleoid, mitochondria, ribosomes and storage granules

Nucleoid

                  Central part of bacteria that contain DNA and RNA in the form of thread like structures called chromosomes

Plasma membrane

                          Plasma membrane is made up of phospholipid bilayer around the cytoplasm and act as a barrier in the transport of materials

Fimbriae

                They are called attachment pili , present all around the cell surface and help in locomotion as well attachment on the surface

Pili

       Similar to fimbriae but are longer in size help in process of conjugation thus called conjugation pili or sex pili also aid in gripping the pili

S-layer

          Two dimensional array of proteins, crystalline appearance present in most of pathogenic bacteria help survival in host by preventing the defense mechanism of host and also act as a partially permeability barrier for large substrate

Flagella

               Extracellular structure protruding from the cell wall and help in locomotion. Flagella made up of protein called flagellin. The arrangement of flagella is different in different species. Some common forms include:

·        Monotrichous- that contain one flagellum in their cell wall

·        Lophotrichous -that contain bunch of flagella at one pole of cell wall

·        Amphitrichous -that contain single flagellum at two poles

·        Peritrichous that- contain multiple flagella all around the cell wall of bacteria

Cytoskeleton

                       Cytoskeleton contain filaments and play important role in cell division, shape determination, protection and polarity determination in bacteria

Endospores

                     Endospores are bacterial survival structures that are resistant to harsh environmental and chemical conditions. They are present in certain species of bacillus and clostridium. Dipicolinic acid is composed of 5% to 15% dry matter that helps in heat resistance.