If you fetch large amounts of data (e.g. over 2MB per request) using HTTP_Client (or HTTP_request), you may get "out of memory" fatal errors, especially if:

1. memory_limit is set to default 8M, and
2. you process multiple pages using single non-reset instance of HTTP_Client object.

This problem can manifest itself by producing fatal error after a couple of cycles of successful page retrieval - but always, if run with the same parameters, after some constant or only slightly variable number of cycles.

In my case the problem was that HTTP_Request (a dependancy of HTTP_Client) was holding in memory all the previously fetched pages of the current session (the 'history' feature). To force HTTP_Request to hold only the most recent page, you need to 'disable' history after creating the HTTP_Client or HTTP_Request object instance:

Hope this helps you.

I needed to find out common transcription factor (TF) binding sites (TFBS) in the structure of the promoters of interferon-regulated genes. I tried several different approaches - starting from the simplest sequence-sequence comparisons using BLAST, ClustalW alignments, and searching each of the promoters for transcription factor binding sites - to compare and find common.

But the easiest way was to use Genomatix's "Gene2Promoter" tool. With it, the whole procedure is extremely simple:
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