You can generally conjoin two phrases of the same grammatical type to form a phrase of that same type, which can go anywhere either single phrase could go. This gives the following three equivalent ways of saying your example. I have indicated with brackets the structure of the conjoined phrase for each version:
[[As Mr. X has replied your email] and [as he has requested the 'PDF files' of the project]], ...
As Mr. X [[has replied your email] and [has requested the 'PDF files' of the project]], ...
As Mr. X has [[replied your email] and [requested the 'PDF files' of the project]], ...