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Non-traditional book publishing, prospering on the Internet, now accounts for over eight times the output of traditional publishing. Non-traditional publishing includes books published by their authors and books representing the reuse of content, most of it not covered by copyright. The result is an heterogeneous, hyper-abundant contemporary book environment where the traditional mixes with the non-traditional and finding books that match a reader’s taste is more difficult than previously and may involve new methods of discovery.

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This paper describes a number of critical challenges faced by digital curation educators and suggests how the choices we make in building educational programs may impact the development of curation as a professional discipline. We focus on curriculum and program building as key steps in defining the educational needs of curators, and we argue for greater collaboration among educators, researchers and practitioners in the field, as a way to speed the emergence of curation as a discipline and to foster the integration of curation programs within libraries and archives.

Methanobactins (MBs) are ribosomally synthesized and post-translationally modified peptides (RiPPs) produced by methanotrophs for copper uptake. The post-translational modification that define MBs is the formation of two heterocyclic groups with associated thioamines from X-Cys dipeptide sequences. Both heterocyclic groups in the MB from Methylosinus trichosporium OB3b (MB-OB3b) are oxazolone groups. The precursor gene for MB-OB3b, mbnA , which is part of a gene cluster that contains both annotated and unannotated genes. One of those unannotated genes, mbnC , is found in all MB operons, and in conjunction with mbnB , is reported to be involved in the formation of both heterocyclic groups in all MBs. To determine the function of mbnC , a deletion mutation was constructed in M. trichosporium OB3b, and the MB produced from the Δ mbn C mutant was purified and structurally characterized by UV-visible absorption spectroscopy, mass spectrometry and solution NMR spectroscopy. MB-OB3b from Δ mbn C was missing the C-terminal Met and also found to contain a Pro and a Cys in place of the pyrrolidiny-oxazolone-thioamide group. These results demonstrate MbnC is required for the formation of the C-terminal pyrrolidinyl-oxazolone-thioamide group from the Pro-Cys dipeptide, but not for the formation of the N-terminal 3-methylbutanol-oxazolone-thioamide group from the N-terminal dipeptide Leu-Cys. IMPORTANCE A number of environmental and medical applications have been proposed for MBs, including bioremediation of toxic metals, nanoparticle formation, as well as for the treatment of copper- and iron-related diseases. However, before MBs can be modified and optimized for any specific application, the biosynthetic pathway for MB production must be defined. The discovery that mbnC is involved in the formation of the C-terminal oxazolone group with associated thioamide but not for the formation of the N-terminal oxazolone group with associated thioamide in M. trichosporium OB3b suggests the enzymes responsible for post-translational modification(s) of the two oxazolone groups are not identical.