Cell

Part:BBa_K1321305

Designed by: Michael Florea   Group: iGEM14_Imperial   (2014-10-08)
Revision as of 23:31, 16 October 2014 by Mf1512 (Talk | contribs)

Gluconacetobacter xylinus ATCC 53582

Gluconacetobacter xylinus is an obligate aerobe, Gram negative bacterial species which produces bacterial cellulose. Strain ATCC 53582 has been reported as one of the highest cellulose-producing strains, and readily produces cellulose with different carbon feedstocks. G.xylinus can be used as platform for engineering novel protein-cellulose composite biomaterials.


G.xylinus ATCC 53582 genome sequence

G.xylinus ATCC 53582 genome was sequenced as a part of Imperial iGEM 2014 project. The genome is approximately 3.5Mbp in size.

Culturing G. xylinus ATCC 53582

G.xylinus ATCC 53582 growth rate varies depending on the culturing conditions. Growth rate is highest when G.xylinus is cultured at 30degC, 180rpm shaking in a well-aerated setting. However, several authors have noted that in shaking conditions, the prevalence of cellulose non-producing mutants (cel- mutants) increases, which causes a decrease in the total yield of produced cellulose. For this reason, when high cellulose production is required, G.xylinus is often grown in static conditions, at 30degC, in a well-aerated setting. In shaking cultures, ATCC 53582 reaches stationary phase in 48-72 hours, whereas in static cultures, depending on the volume of the medium, it can take up to 10 days. When grown on HS-agar plates at 30degC, colonies become visible within 48-72 hours. Although several different media have been used for culturing G.xylinus, the most commonly used is Hestrin-Schramm (HS) medium. HS medium contains the following components (for a protocol for G.xylinus culturing, see (G.xylinus media and culturing on Imperial 2014 wiki): 2% (w/v) glucose 0.5% (w/v) yeast extract 0.5% (w/v) peptone 0.27% (w/v) Na2HPO4 0.15% (w/v) citric acid

Cellulose productivity of G.xylinus ATCC 53582 in HS-glucose

ATCC 53582 has been reported as one of the highest cellulose-producing strains (see Figure 1 for comparison of cellulose productivity of ATCC53582 and KI strains on HS-glucose medium and experimental details). Because G.xylinus is an obligate aerobe, cellulose final yield strongly depends on the surface-area-to-volume ratio of the liquid culture it is grown in, as well as aeration efficiency of the system. When grown at 30degC standing, in a 250ml conical flask, sealed with a foam bun, in 50ml HS-glucose medium, ATCC 53582 produces up to 0.6g of cellulose (Figure 1). As 50ml HS-glucose medium contains 1g of glucose, a yield of 0.6g represents 60% glucose to cellulose conversion efficiency.

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Feedstocks for G.xylinus ATCC 53582

G.xylinus is commonly grown on HS-glucose. However, it can readily use other carbon feedstocks, including sucrose and glycerol. have found that ATCC 53582 cellulose productivity is highest when grown on glycerol (see Figure 2.), although the effects of routine culturing of ATCC 53582 on HS-glycerol media are unknown.

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Natural antibiotics resistance of G.xylinus ATCC 53582

Using optimal antibiotics concentrations is critical for selection of transformed cells while not inhibiting the cell growth. G.xylinus ATCC 53582 is not resistant to kanamycin and ampicillin in concentrations normally used for E.coli (50µg/ml and 100µg/ml respectively), however is resistant to chloramphenicol (at 35µg/ml; see Figure 5 for an experiment of ATCC 53582 natural antibiotic concentrations, experimental details, and comparison of ATCC to KI strain).

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Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    COMPATIBLE WITH RFC[1000]


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