Background: One of the most fundamental problems, which remain unsolved, is how entirely
new gene (EntNew gene) was produced, which is totally different gene from any previously existing
gene. On the other hand, we have proposed GC-NSF(a) hypothesis on formation of EntNew
gene/protein, assuming that EntNew gene is generated from non-stop frame on antisense strand of GCrich
Objective: The objective of this study is to obtain direct evidence clearly supporting the GC-NSF(a)
hypothesis through computer analysis of gene/protein databases of GC-rich microbial genomes.
Method: In order to get direct evidence for the hypothesis, every base sequence encoded by GC-rich
P. aeruginosa PAO1 genome (GC content=66.6%) was transformed into antisense sequence (GCNSF(
a)). NSF(a) is a non-stop frame codon sequence on antisense strand in the reading frame corresponding
with gene on sense strand. AAS of every imaginary protein encoded by the GC-NSF(a) was
homology-searched against all extant proteins encoded by the same genome. Program version 2.2.30+
of BLASTP in NCBI for computational investigation was used in the homology-search.
Results: From the results, it was found that AAS encoded by GC-NSF(a) of tal gene has sufficient homology
with AAS encoded by ftsZ gene. In addition to another result from the P. aeruginosa genome,
three cases showing sufficient homology between AAS encoded by GC-NSF(a) and AAS of extant
protein were also obtained from the results similarly analyzed with 57 GC-rich microbial genomes.
Conclusion: Thus, we conclude that EntNew gene encoding EntNew protein has been generated from
GC-NSF(a), according to the GC-NSF(a) hypothesis.