U can predict 3° structure of protiens if u have ammino acid sequence in FASTA codes which is easily available on uniprot. There are many online tools available online for the purpose.. Try using expasy u can i have seen people derermining tertiary structure using autodock. Swiss PDB is most easy tool to use to determine secondary structure if u're intrested.. Good luck

You can try this: https://www.expasy.org/proteomics/protein_structure

I know some peope, who are using swiss model: https://swissmodel.expasy.org/interactive

Do you want to check, if you can crystallize it? For this people are using: http://services.mbi.ucla.edu/SER/

Good luck,

Linda

There are several, each employing different algorithms. Here are some:

"PredictProtein started out by predicting secondary structure and returning families of related proteins. [...]  we have substantially expanded the breadth of structural annotations, e.g. by adding predictions of non-regular secondary structure and intrinsically disordered regions, disulphide bridges and inter-residue contacts, and finally by also covering trans-membrane beta barrels structures. We have also added important resources for the prediction of protein function, e.g. assisting in the annotation of subcellular localization (LocTree, LocTree2, NLSpred), identifying protein-protein interaction sites (ISIS) and protein-DNA binding sites (DISIS & SomeNA to be released shortly)." : https://www.predictprotein.org/

Expasy has several links to web tools for unreavealing protein structure depending on your goal: https://www.expasy.org/proteomics/protein_structure

"This server allow to predict the secondary structure of protein's from their amino acid sequence": http://imtech.res.in/raghava/apssp/

"This server predicts secondary structure of protein from the amino acid sequence": http://www.biogem.org/tool/chou-fasman/

And a more extensive list of softwares is available on wikipedia: https://en.wikipedia.org/wiki/List_of_protein_structure_prediction_software

Thanks Linda and Terezinha. I have used other tools of expasy but not swissmodel. What if I want to introduce some mutations and then check the changes in structure of the protein, is that possible in Swissmodel? ('cause it asks for Uniprot ID)

you can use Rosetta or Robetta server. depending on the requirement  

Hello

For 3D Structure and Cavity you can use:

CASTp, Autodock vina, Swissmodel, Qsite, Chimera, RasMol or JMOL, MOE, BIOVIA Discovery Studio.

.

I-Tasser is for predicting protein structure.

Good Luck