Part:BBa_K2740018

CR1 nifX

CR1 nifX encodes nitrogen fixation protein NifX that favors the insertion of molybdenum-iron protein cofactors into nitrogenase.

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]

Parameter of Protein

Number of amino acids: 129

Molecular weight: 14126.33

Theoretical pI: 6.51

Amino acid composition:
Ala (A)  16  12.4%
Arg (R)   7    5.4%
Asn (N)   4   3.1%
Asp (D)   3   2.3%
Cys (C)   1    0.8%
Gln (Q)   7    5.4%
Glu (E)  11    8.5%
Gly (G)  10    7.8%
His (H)   5    3.9%
Ile (I)    10   7.8%
Leu (L)  10    7.8%
Lys (K)   6    4.7%
Met (M)  5     3.9%
Phe (F)   7     5.4%
Pro (P)   4     3.1%
Ser (S)   7     5.4%
Thr (T)   5     3.9%
Trp (W)  1     0.8%
Tyr (Y)   0    0.0%
Val (V)  10    7.8%
Pyl (O)   0     0.0%
Sec (U)   0    0.0%

 (B)   0         0.0%
(Z)   0   0.0%
(X)   0         0.0%

 

Total number of negatively charged residues (Asp + Glu): 14
Total number of positively charged residues (Arg + Lys): 13

Atomic composition:

Carbon      C           627
Hydrogen    H         1006
Nitrogen    N            178
Oxygen      O          181
Sulfur      S               6

Formula: C627H1006N178O181S6
Total number of atoms: 1998

Extinction coefficients:

Extinction coefficients are in units of  M-1 cm-1, at 280 nm measured in water.

Ext. coefficient     5500
Abs 0.1% (=1 g/l)   0.389, assuming all pairs of Cys residues form cystines

 

Ext. coefficient     5500
Abs 0.1% (=1 g/l)   0.389, assuming all Cys residues are reduced

Estimated half-life:

The N-terminal of the sequence considered is M (Met).

The estimated half-life is: 30 hours (mammalian reticulocytes, in vitro).
>20 hours (yeast, in vivo).
>10 hours (Escherichia coli, in vivo).

 

Instability index:

The instability index (II) is computed to be 47.67
This classifies the protein as unstable.

 

Aliphatic index: 95.35

Grand average of hydropathicity (GRAVY): 0.051

Design Notes

Nitrogenase is a complex enzyme system consisting of nine protein components. Additionally, to maintain stoichiometry of these protein components is an essential requirement for nitrogenase biosynthesis and activity. However, there is only one copy of each structure gene present in the nif gene cluster. Therefore, cloning each of these nif genes and setting as independent part can facilitate the regulation of balancing expression ratios from the transcription and/or translation level(s) when they are heterogeneously expressed in non-diazotrophic hosts.