The genome sequence of Propionibacterium acidipropionici provides insights into its biotechnological and industrial potential.
BACKGROUND
Synthetic biology allows the development of new biochemical pathways for the production of chemicals from renewable sources. One major challenge is the identification of suitable microorganisms to hold these pathways with sufficient robustness and high yield. In this work we analyzed the genome of the propionic acid producer Actinobacteria Propionibacterium acidipropionici (ATCC 4875).


RESULTS
The assembled P. acidipropionici genome has 3,656,170 base pairs (bp) with 68.8% G + C content and a low-copy plasmid of 6,868 bp. We identified 3,336 protein coding genes, approximately 1000 more than P. freudenreichii and P. acnes, with an increase in the number of genes putatively involved in maintenance of genome integrity, as well as the presence of an invertase and genes putatively involved in carbon catabolite repression. In addition, we made an experimental confirmation of the ability of P. acidipropionici to fix CO2, but no phosphoenolpyruvate carboxylase coding gene was found in the genome. Instead, we identified the pyruvate carboxylase gene and confirmed the presence of the corresponding enzyme in proteome analysis as a potential candidate for this activity. Similarly, the phosphate acetyltransferase and acetate kinase genes, which are considered responsible for acetate formation, were not present in the genome. In P. acidipropionici, a similar function seems to be performed by an ADP forming acetate-CoA ligase gene and its corresponding enzyme was confirmed in the proteome analysis.


CONCLUSIONS
Our data shows that P. acidipropionici has several of the desired features that are required to become a platform for the production of chemical commodities: multiple pathways for efficient feedstock utilization, ability to fix CO2, robustness, and efficient production of propionic acid, a potential precursor for valuable 3-carbon compounds.
Laboratório de Genômica e Expressão, Departamento de Genética e Evolução, Instituto de Biologia, Universidade Estadual de Campinas, CP 6109, Campinas, 13083-970, São Paulo, Brazil.
Lucas P
LP
Parizzi
Maria Carolina B
MC
Grassi
Luige A
LA
Llerena
Marcelo F
MF
Carazzolle
Verônica L
VL
Queiroz
Inês
I
Lunardi
Ane F
AF
Zeidler
Paulo J P L
PJ
Teixeira
Piotr
P
Mieczkowski
Johana
J
Rincones
Gonçalo A G
GA
Pereira
D000106:Acetate-CoA Ligase / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001482:Base Composition; D001483:Base Sequence; D002245:Carbon Dioxide / Q000378:metabolism; D016680:Genome, Bacterial; D007218:Industrial Microbiology; D053858:Metabolic Networks and Pathways; D008969:Molecular Sequence Data; D010957:Plasmids; D011422:Propionates / Q000378:metabolism*; D011424:Propionibacterium / Q000235:genetics* / Q000378:metabolism*; D011766:Pyruvate Carboxylase / Q000235:genetics / Q000378:metabolism; D043324:beta-Fructofuranosidase / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D011422:Propionates; D002245:Carbon Dioxide; D043324:beta-Fructofuranosidase; D000106:Acetate-CoA Ligase; D011766:Pyruvate Carboxylase; C029658:propionic acid