Sorry, Not Gonna Happen, not on a G5.
Here are the System Requirements for CS 5.5 Master Suite for Mac OS
https://store1.adobe.com/store/en_us/popup/software/creativesuite/mastercollection5_5/systemreqs.html
Multicore Intel® processor with 64-bit support
Mac OS X v10.5.8 or v10.6; Mac OS X v10.6 required for Adobe Flash® Builder™ 4.5 Premium and Flash Builder integration with Flash Catalyst and Flash Professional; Mac OS X v10.6.3 required for GPU-accelerated performance in Adobe Premiere® Pro
2GB of RAM (4GB or more recommended)
26.3GB of available hard-disk space for installation; additional free space required during installation (cannot install on a volume that uses a case-sensitive file system or on removable flash storage devices)
1280×900 display (1280×1024 recommended) with qualified hardware-accelerated OpenGL graphics card, 16-bit color, and 256MB of VRAM
Adobe-certified GPU card for GPU-accelerated performance in Adobe Premiere Pro
Some GPU-accelerated features in Adobe Photoshop require graphics support for Shader Model 3.0 and OpenGL 2.0
7200 RPM hard drive for editing compressed video formats; RAID 0 for uncompressed
Core Audio–compatible sound card
DVD-ROM drive compatible with dual-layer DVDs (SuperDrive for burning DVDs; external Blu-ray burner for creating Blu-ray Disc media)
Java™ Runtime Environment 1.6
Eclipse™ 3.6.1 Cocoa version required for plug-in installation
QuickTime 9 software required for QuickTime and multimedia features
Adobe Flash® Player 10 software required to export SWF files and to play back DVD projects exported as SWF files
Broadband Internet connection required for online services and to validate Subscription Edition (if applicable) on an ongoing basis*