Off topic:Reformatting Fasta Files

Question

[Gritz122]

Hi I would like to know the awk command for changing

>AY156743.1 HIV-1 clone P.ENV from USA envelope glycoprotein (env) gene, partial cds
TCAATTACTGGTAAATGGCAGTCTAGCAGAAGAAGARGTAGTAATTAGATCTGAAAATTTCACGAACAAT
GCTAAAAYCATAATAGTACAGCTGAAAGAMCCTGTAGAAATTAATTGTACAAGACCCAACAACWATACAR
G.....

to

>AY156743_P
TCAATTACTGGTAAATGGCAGTCTAGCAGAAGAAGARGTAGTAATTAGATCTGAAAATTTCACGAACAAT
GCTAAAAYCATAATAGTACAGCTGAAAGAMCCTGTAGAAATTAATTGTACAAGACCCAACAACWATACAR
G.....

or simply deleting:

ENV from USA envelope glycoprotein (env) gene, partial cds

thanks