User:Karl Oberholser/Sandbox2

From Proteopedia

Jump to: navigation, search

Histones HMfA and HMfB from Methanothermus fervidus

"The hyperthermophilic archaeon Methanothermus fervidus contains two small basic proteins, HMfA (68 amino acid residues) and HMfB (69 residues)that share a common ancestry with the eukaryal nucleosome core histones H2A, H2B, H3, and H4. HMfA and HMfB have sequences that differ at 11 locations, they have different structural stabilities, and the complexes that they form with DNA have different electrophoretic mobilities." [1]


Comparison of Structures

HMfA Seq: MGELPIAPIG RIIKNAGAER VSDDARIALA KVLEEMGEEI ASEAVKLAKH AGRKTIKAED IELARKMFK
HMfB Seq: MELPIAPIGR IIKDAGAERV SDDARITLAK  ILEEMGRDIA  SEAIKLARHA  GRKTIKAEDI  ELAVRRFKK

Comparing the above sequences one can see that an important difference is that A has a glycine at position 2 which is lacking in B. In addition to that deletion, there are a number of substitutions which creates differences in the sequence of the two peptides. As a consequence of this similarity of primary structure, as shown in the two applets below, the tertiary structures of both peptides are quite similar (, ). Also the location of the nonpolar residues within the tertiary structure are similarly located , .

HMfA, PDB ID:1hta

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)

Karl Oberholser

Personal tools