| P31891 | n/a | 4iub | S3F | S | 1003 | e4iubL1 | alpha-helical domain in nickel-iron hydrogenase, large subunit | alpha-helical domain in nickel-iron hydrogenase, large subunit | alpha-helical domain in nickel-iron hydrogenase, large subunit | NiFeSe_Hases |
| P31891 | n/a | 4iub | S3F | S | 1003 | e4iubL4 | FAD-linked reductases, C-terminal domain-like | Ni-Fe binding domain in nickel-iron hydrogenase large subunit | Ni-Fe binding domain in nickel-iron hydrogenase large subunit | NiFeSe_Hases |
| P31891 | n/a | 4iuc | S3F | S | 1003 | e4iucL1 | alpha-helical domain in nickel-iron hydrogenase, large subunit | alpha-helical domain in nickel-iron hydrogenase, large subunit | alpha-helical domain in nickel-iron hydrogenase, large subunit | NiFeSe_Hases |
| P31891 | n/a | 4iuc | S3F | S | 1003 | e4iucL4 | FAD-linked reductases, C-terminal domain-like | Ni-Fe binding domain in nickel-iron hydrogenase large subunit | Ni-Fe binding domain in nickel-iron hydrogenase large subunit | NiFeSe_Hases |
| P31891 | n/a | 4iud | S3F | S | 1003 | e4iudL1 | alpha-helical domain in nickel-iron hydrogenase, large subunit | alpha-helical domain in nickel-iron hydrogenase, large subunit | alpha-helical domain in nickel-iron hydrogenase, large subunit | NiFeSe_Hases |
| P31891 | n/a | 4iud | S3F | S | 1003 | e4iudL4 | FAD-linked reductases, C-terminal domain-like | Ni-Fe binding domain in nickel-iron hydrogenase large subunit | Ni-Fe binding domain in nickel-iron hydrogenase large subunit | NiFeSe_Hases |