Clostridium ljungdahlii is an anaerobic homoacetogen, able to ferment sugars, other organic compounds, or CO ₂ /H ₂ and synthesis gas (CO/H ₂ ). The latter feature makes it an interesting microbe for the biotech industry, as important bulk chemicals and proteins can be produced at the expense of CO ₂ , thus combining industrial needs with sustained reduction of CO and CO ₂ in the atmosphere. Sequencing the complete genome of C. ljungdahlii revealed that it comprises 4,630,065 bp and is one of the largest clostridial genomes known to date. Experimental data and in silico comparisons revealed a third mode of anaerobic homoacetogenic metabolism. Unlike other organisms such as Moorella thermoacetica or Acetobacterium woodii , neither cytochromes nor sodium ions are involved in energy generation. Instead, an Rnf system is present, by which proton translocation can be performed. An electroporation procedure has been developed to transform the organism with plasmids bearing heterologous genes for butanol production. Successful expression of these genes could be demonstrated, leading to formation of the biofuel. Thus, C. ljungdahlii can be used as a unique microbial production platform based on synthesis gas and carbon dioxide/hydrogen mixtures.

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The genome of Bacillus licheniformis DSM13 consists of a single chromosome that has a size of 4,222,748 base pairs. The average G+C ratio is 46.2%. 4,286 open reading frames, 72 tRNA genes, 7 rRNA operons and 20 transposase genes were identified. The genome shows a marked co-linearity with Bacillus subtilis but contains defined inserted regions that can be identified at the sequence as well as at the functional level. B. licheniformis DSM13 has a well-conserved secretory system, no polyketide biosynthesis, but is able to form the lipopeptide lichenysin. From the further analysis of the genome sequence, we identified conserved regulatory DNA motives, the occurrence of the glyoxylate bypass and the presence of anaerobic ribonucleotide reductase explaining that B. licheniformis is able to grow on acetate and 2,3-butanediol as well as anaerobically on glucose. Many new genes of potential interest for biotechnological applications were found in B. licheniformis; candidates include proteases, pectate lyases, lipases and various polysaccharide degrading enzymes.

The product of the selD gene from Escherichia coli catalyses the formation of an activated selenium compound which is required for the synthesis of Sec‐tRNA (Sec, selenocysteine) from Ser‐tRNA and for the formation of the unusual nucleoside 5‐methylaminomethyl‐2‐selenouridine in several tRNA species. selD was overexpressed in a T7 promoter/polymerase system and purified to apparent homogeneity. Purified SELD protein is a monomer of 37 kDa in its native state and catalyses a selenium‐dependent ATP‐cleavage reaction delivering AMP and releasing the β‐phosphate as orthophosphate. The γ‐phosphate group of ATP was not liberated in a form able to form a complex with molybdate. It was precluded that any putative covalent or non‐covalent ligand of SELD not removed during purification participated in the reaction. In a double‐labelling experiment employing [⁷⁵Se]selenite plus dithiothreitol and [γ‐³²P]ATP the ⁷⁵Se and ³²P radioactivities co‐chromatographed on a poly(ethyleneimine)‐cellulose column. No radioactivity originating from ATP eluted in this position when [α‐³²P]ATP or [β‐³²P]ATP or [¹⁴C]ATP were offered as substrates. The results support the speculation that the product of SELD is a phosphoselenoate with the phosphate moiety derived phosphoselenoate from the γ‐phosphate group of ATP. The α,β cleavage of ATP is also supported by the finding that neither adenosine 5′‐[α,β‐methylene]triphosphate nor adenosine 5′‐[β,γ‐methylene]triphosphate served as substrates in the reaction.