Comparative analyses and structural insights of the novel cytochrome P450 fusion protein family CYP5619 in Oomycetes

Phylogenetic and structural analysis of P450 proteins fused to peroxidase/dioxygenase has not been reported yet. We present phylogenetic and in silico structural analysis of the novel P450 fusion family CYP5619 from the deadliest fish pathogenic oomycete, Saprolegnia diclina. Data-mining and annotation of CYP5619 members revealed their unique presence in oomycetes. CYP5619 members have the highest number of conserved amino acids among eukaryotic P450s. The highest number of conserved amino acids (78%) occurred in the peroxidase/dioxygenase domain compared to the P450 domain (22%). In silico structural analysis using a high-quality CYP5619A1 model revealed that CYP5619A1 has characteristic P450 structural motifs including EXXR and CXG. However, the heme-binding domain (CXG) in CYP5619 members was found to be highly degenerated. The in silico substrate binding pattern revealed that CYP5619A1 have a high affinity to medium chain fatty acids. Interestingly, the controlling agent of S. diclina malachite green was predicted to have the highest binding affinity, along with linoleic acid. However, unlike fatty acids, none of the active site amino acids formed hydrogen bonds with malachite green. The study’s results will pave the way for assessing CYP5619A1’s role in S. diclina physiology, including the nature of malachite green binding.

Protocol publication

[…] P450 motifs EXXR and CXG sequence logos were generated as described elsewhere,. Briefly, CYP5619 family members were aligned using ClustalW multiple alignment using MEGA7. After sequence alignment the EXXR and CXG region amino acids (4 and 16 amino acids respectively), were selected and entered in the WebLogo program (http://weblogo.berkeley.edu/logo.cgi). As a selection parameter, the image format was selected as PNG (bitmap) at 300 dpi resolution. The generated EXXR and CXG logos were used for analysis and compared to the different P450 family EXXR and CXG logos that have been published and are available to the public,. […]