TABLE 1.
Protein crystal systems and their NLO propertiesa.
| Number | Protein and crystal system | Space group | Protein Data Bank (PDB) identification code | SHG | Fluorescence |
|---|---|---|---|---|---|
| 1 | Lysozyme (Triclinic) | P1 | 7LYZ | + | + |
| 2 | Endo–1,4–3–D–xylanase II (Monoclinic) | C2 | 1XYN | + | + |
| 3 | Lysozyme (Tetragonal) | P43212 | 2LZM | − | + |
| 4 | Thaumatin (Tetragonal) | P41212 | 2PE7 | − | + |
| 5 | RPE65 (Hexagonal) | P65 | 3KVC | − | + |
| 6 | Glucose isomerase (Orthorhombic) | I222 | 6XIV | ? | + |
| 7 | Ribonuclease A (Orthorhombic) | P212121 | 1RTA | − | − |
| 8 | Bacteriorhodopsin (Hexagonal)b | P63 | 1AP9 | + | + |
| 9 | Photosynthetic reaction center (Tetragonal) | P43212 | 6PRC | − | + |
| 10 | Rhodopsin (trigonal) | P3112 | 2I37 | ? | + |
– Protein crystals were identified by their X–ray diffraction patterns and their assignment to space groups was accomplished by crystallographic data processing. These crystals were further assessed for their SHG properties by using TPM imaging as described in Materials and Methods. Unless otherwise stated, the excitation wavelength for these experiments was 850 nm.
A plus or minus sign indicates a SHG or a TPEF signal observed (+) or not (−). A question mark indicates that SHG was too weak to be confirmed unambiguously. The third column shows the PDB ID of protein crystal structures deposited by our laboratory or others that correspond to the protein crystal systems used in this study.
– Space group determination was not performed in this study.