Myxococcus xanthus

Schley, C., Altmeyer, M.O., Swart, R., Muller, R., Huber, C.G. (2006). Proteome analysis of Myxococcus xanthus by off-line two-dimensional chromatographic separation using monolithic poly-(styrene-divinylbenzene) columns combined with ion-trap tandem mass spectrometry. J. Proteome Res. 5, 2760-2768. 

Julien, B. and Shah, S. (2002) Heterologous expression of epothilone biosynthetic genes in Myxococcus xanthus. Antimicrobial Agents and Chemotherapy, 46 (9), 2772-2778. 

More recently two functionally redundant Sfp-type PPTase, MxPptl and MxPptZ, have been found to differentially activate biosynthetic pathways in Myxococcus xanthus MxPptl and MxPptZ exhibit broad substrate specificity as supported by the fact that the complex PKS-NRPS hydrids epothilone and myxothiazol from Sorangium cellulosum and Stigmatella aurantiaca, respectively, could be expressed in M. xanthus without the need for an external PPTase. 

McCleary, W.R. Zusman, D.R. FrzE of Myxococcus xanthus is homologous to both CheA and CheY of Salmonella typhimurium. Proc. Natl. Acad. Sci. USA, 87, 5898-5902 (1990)... 

Williams, R.L. Oren, D.A. Munoz-Dorado, J. Inoue, S. Inoue, M. Arnold, E. Crystal structure of Myxococcus xanthus nucleoside diphosphate kinase and its interaction with a nucleotide substrate at 2.0 A resolution. J. Mol. Biol., 234, 1230-1247 (1993)... 

Plamann, L. and Kaplan, H.B., Cell-density sensing during early development in Myxococcus xanthus, in Cell-Cell Signaling Bacteria, Dunny, G.M. and Winans, S.C., Eds., ASM Press, Washington, D.C., 1999, 67. 

Spormann, A. M., Gliding motility in bacteria insights from studies of Myxococcus xanthus, Microbiol. Mol. Biol. Rev., 63, 621, 1999. 

Kuspa, A., Plamann, L., and Kaiser, D., Identification of heat-stable A-factor from Myxococcus xanthus, J. Bacteriol., 174, 3319, 1992. 

Velicer GJ, Yu YT (2003) Evolution of novel cooperative swarming in the bacterium Myxococcus xanthus. Nature 425 75-78... 

Bordetella pertussis AF366576 — Myxococcus xanthus M34114 8 ... 

Myxococcus coralloides Myxococcus xanthus Neisseria meningitidis Nitrobacter sp. 

Figure 5.1 PolyP granules in Myxococcus xanthus (magnification 110 000 x).

Agrobacterium tumefaciens Brucella melitensis Burkholderia fungorum (2) Campylobacter jejuni Caulobacter crescentus Chlorobium tepidum Chloroflexus aurantiacus Deinococcus radiodurans Magnetospirillum magnetotacticum (2) Mesorhizobium loti (2) Methanosarcina acetivorans (2)b Methanosarcina mazei (2)b Mycobacterium tuberculosis Myxococcus xanthus Nostoc punctiforme (2)... 

Evidence for the participation of (p)ppGpp and PolyP-dependent systems in the regulation of development of prokaryotes with a complicate life cycle, Myxococcus coralloides (Gonzales et al, 1989) and Myxococcus xanthus (Singler and Kaiser, 1995 Harris et al., 1998), has also been obtained. 

B. Z. Harris, D. Kaiser and M. Singer (1998). The guanosine nucleotide (p)ppGpp initiates development and A-factor production in Myxococcus xanthus. Genes Dev., 12, 1022-1035. 

M. Singler and D. Kaiser (1995). Ectopic production of guanosine penta- and tetraphosphate can initiate early developmental gene expression in Myxococcus xanthus. Genes Dev., 9, 1633-1644. 

The opposite is true, however, for the introduction of the 12,13-cw double bond in epothilone. Expression of the epo PKS in the heterologous hosts Myxococcus xanthus and, recently, Escherichia coli resulted, in both cases, in the production of epothilones C and D (containing the 12,13-cu double bond) (5, 7), suggesting that the epo PKS itself directs the introduction of the double bond during the synthesis by a module other than module 4. Further evidence to support this hypothesis will be presented below. 

Figure 4 Secondary metabolites produced by the myxobacterial model strain Myxococcus xanthus DK1622. Among the 18 putative PKS/NRPS biosynthetic pathways identified in the 9.1 Mb M. xanthus genome sequence, five biosynthetic gene clusters have been correlated to specific metaboiites. Oniy one member of the identified compound famiiies is shown DKxanthene-534 (9), myxovirescin Ai (10), myxochromide A2 (11), myxaiamid B (12), and myxocheiin A (13).

Figure 10 Nonribosomal peptide biosynthesis in myxobacteria (a). Biosynthesis of saframycin Mx1 (30) in Myxococcus xanthus DM504/15. The tetramoduiar assembiy iine foiiows textbook biochemistry, except for the unusuai reductive chain reiease by the terminai Red domain. The iinear peptide chain (27) then undergoes severai cyciization steps (the underiying mechanisms are not fuiiy understood) and is further decorated with functionai groups (highiighted in gray) by enzyme activities, which have not been identified to date. Based on the absence of E domains in the assembiy iine and the absoiute configuration of the end product 30, an L-configuration was assigned to the incorporated amino acids.

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