a Whole Genome Array Approach - Jacobs University

Background
planctomycete Gemmata obscuriglobus UQM2246 T only 11 sulphatases are present
(1.37 Mb) (Woebken et al. 2007). Another marine organism, Zobellia galactanivorans,
belonging to the CFB group has around 70 genes annotated as sulphatases (Gurvan Michel,
personal communication).
Sulphatases are widespread enzymes found in Bacteria, Archaea and Eukarya. They are
involved in various metabolic processes, ranging from a sulphate starvation response in
bacteria to hormone biosynthesis and the modulation of developmental cell signalling in
mammals (Parenti 1997). In humans, their biological relevance is particularly underlined by
their involvement in several inherited diseases, such a mucopolysaccaridoses. It is known that
sulphatases act on a broad diversity of substrates, which leads to their classification by the
IUBMB into 17 classes (from EC 3.1.6.1 to EC 3.1.6.18) (Berteau et al. 2006). The role of the
sulphatases in R. baltica is not yet clearly understood.
Investigations of the 110 sulphatases in R. baltica based on the transcriptome and proteome
level revealed that at least a fraction of them are expressed (Gade et al. 2005; Gade et al.
2005; Würdemann 2006). Sulphatase activity studies performed at the University of Graz
(Wallner et al. 2004), show a high enantioselective sec-alkyl sulphatase activity with retention
of configuration when several substrates where tested on resting whole cells of R. baltica
In summary, the data on the nature of substrates utilised as carbon sources by R. baltica and
the high numbers of sulphatase genes found in the genome and the proven activity of at least
some of them suggest that sulphatases are metabolically important in R. baltica and could
play a role in the efficient degradation of sulphated glycopolymers. Such compounds (e.g.
carrageen) are abundant in marine environments in the form of phytodetrital macroaggregates
(“marine snow”), and Planctomycetes have been shown to be components of the microbial
communities on such aggregates (Glöckner et al. 2003; Woebken et al. 2007).
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