The extra-large cavities of zeolite-like metal-organic frameworks (ZMOFs) offer great potential for their exploration in applications pertinent to larger molecules, like porphyrins. The anionic nature of the framework allowed for facile in situ encapsulation of a cationic free-base porphyrin, and the alpha-cage of our (In-imidazoledicarboxylate)-based rho-ZMOF is ideally suited to the isolation of one porphyrin molecule per cage, which prevents the oxidative self-degradation associated with self-dimerization common in homogeneous catalysis and upon aggregation in solid supports like mesoporous silicates or polymers. The encapsulation of a free-base porphyrin [5,10,15,20-tetrakis(1-methyl-4- pyridinio)porphyrin] and the stability of the rho-ZMOF to metalation conditions, allows for the preparation of a variety of metalloporphyrins (i.e., Mn, Cu, Co, Zn ions) with the ZMOF serving as a platform. The Mn-metallated porphyrin encapsulated in rho-ZMOF shows catalytic activity toward the oxidation of cyclohexane, with turn-over numbers, to the best of our knowledge, higher than reported for similar heterogeneous systems, and our system can be recycled up to 11 cycles, which represents a longer lifetime than reported for any other system.

Two novel porous anionic zeolite-like metal-organic frameworks, rho-ZMOF and sod-ZMOF, have been synthesized by metal-ligand-directed assembly of rigid and directional tetrahedral building units, InN4 synthesized in situ, and doubly deprotonated bis(bidentate) imidazoledicarboxylic acid ligands (HImDC) in the presence of different structure directing agents (SDAs).

Haem-containing proteins such as haemoglobin and myoglobin play an essential role in oxygen transport and storage. Comparison of the amino-acid sequences of globins from Bacteria and Eukarya suggests that they share an early common ancestor, even though the proteins perform different functions in these two kingdoms. Until now, no members of the globin family have been found in the third kingdom, Archaea. Recent studies of biological signalling in the Bacteria and Eukarya have revealed a new class of haem-containing proteins that serve as sensors. Until now, no haem-based sensor has been described in the Archaea. Here we report the first myoglobin-like, haem-containing protein in the Archaea, and the first haem-based aerotactic transducer in the Bacteria (termed HemAT-Hs for the archaeon Halobacterium salinarum, and HemAT-Bs for Bacillus subtilis). These proteins exhibit spectral properties similar to those of myoglobin and trigger aerotactic responses.