Convert rows into columns
===

I have a file in rows as below and would like to convert into two column format.

    >00000_x1688514
    TGCTTGGACTACATATGGTTGAGGGTTGTA
    >00001_x238968
    TGCTTGGACTACATATTGTTGAGGGTTGTA
    ...

Desired output is

    >00000_x1688514 TGCTTGGACTACATATGGTTGAGGGTTGTA
    >00001_x238968 TGCTTGGACTACATATTGTTGAGGGTTGTA
    ...

I would appreciate any help. Thanks.
    