TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Method: In the method above, the biocatalyst provided is selected to convert at least one lignin derived organic compound consisting of p-coumaryl alcohol, coniferyl alcohol, sinapyl alcohol, benzoate, 4-hydroxybenzoate, p-coumarate, vanillate, or other monomeric aromatic compounds of lignin origin into the biofuel precursor. The culture medium includes acetate, and where the biocatalyst is selected to convert the feedstock with the at least two sugars and the acetate into the biofuel precursor. The biocatalyst is selected to convert at least 80-99% of the feedstock with the at least two sugars and the acetate into the biofuel precursor. The biocatalyst provided includes DNA comprising natural DNA. The byproducts account for less than 5% of the total product in the fermentation broth. Preferably, the byproducts are selected from acetate, lactate, butyrate, isobutyrate, acetolactate, acetoin, ethanol, isopentanol, or isobutyrylaldehyde. The biocatalyst is operable at a pH of 2-8 to produce the biofuel precursor. It retains 50-100% productivity in the presence of a second pH value, where the second pH value represents an increase or decrease from a first pH value. The biocatalyst is selected to have a recoverable productivity from a sudden change of 2-3 pH units from the first pH value. It is also operable within a temperature of 20-50 degrees C to produce the biofuel precursor. The biocatalyst retains 50-100% productivity in the presence of a second temperature value, where the second temperature value represents an increase or decrease from a first temperature value. It is also provided is selected to have a recoverable productivity from a sudden change of 10-30 degrees C from the first temperature. The biocatalyst provided is operable in a medium including mineral salts comprising major and minor bioelements provided in addition to the feedstock, where the medium further includes vitamins. The biocatalyst provided is selected to have a growth rate of at least 0.4-1.0/hour. The biocatalyst provided is a facultative anaerobic biocatalyst operable at dissolved oxygen concentrations across a range of 0-0.5% air saturation to produce the biofuel precursor. The facultative anaerobic biocatalyst has a productivity that recovers from an exposure to more than 5% air saturation. The biocatalyst is selected to have at least 3-11 properties above. It is selected to convert the feedstock into the biofuel precursor at a yield of at least 85-99% theoretical yield. The biocatalyst is selected to have the productivity of at least 1.5-3.5 grams biofuel precursor/gram cell dry weight/hour. The biocatalyst is selected to have the titer equivalent to a lower one of (i) a solubility limit of the biofuel precursor in water under the process conditions, and (ii) 2.5-15% (w/w) of the biofuel precursor in water. The biocatalyst is converted to a co-product and where the co-product is feed grade. The byproducts account for less than 5% of the total product in the fermentation broth. Preferably, the biofuel precursor is isobutanol and the isobutanol meets specifications in American Society for Testing and Materials (ASTM) D 1719-05. The biocatalyst contains no DNA markers. The biofuel precursor comprises a 14C/12C ratio of 1:0 to 0:11. The method further comprises a biocatalyst operable at dissolved oxygen concentrations from 0-0.01% air saturation. Alternatively, making a biofuel precursor comprises: (a) providing a biocatalyst selected to convert a feedstock into the biofuel precursor at a yield of at least 80% theoretical yield, a productivity of at least 0.75 grams biofuel precursor/L/hour, and a titer equivalent to a lower one of (i) a solubility limit of the biofuel precursor in water under the process conditions and (ii) 2% (w/w) of the biofuel precursor in water; and (b) cultivating the biocatalyst in a culture medium until a recoverable quantity of the biofuel precursor is produced; and recovering the biofuel precursor. The biocatalyst is converted to a co-product and where the co-product is feed grade. Alternatively, making a biofuel precursor comprises: (a) providing a feedstock comprising a sugar selected from: (i) a six-carbon sugar; (ii) a six-carbon sugar oligomer; and/or (iii) a five-carbon sugar, where the sugar is obtained from starch, cellulose, hemicellulose, or pectin; (b) contacting the feedstock of (a) with a biocatalyst that converts the feedstock into a biofuel precursor at: (i) a yield of at least 68% theoretical yield; (ii) a productivity of at least 0.75 grams biofuel precursor/L/hour change; and (iii) a lower one of (1) a solubility limit of the biofuel precursor in water under the process conditions, and (2) 1.6% (w/v) of the biofuel precursor in water; and (c) recovering the biofuel precursor. The six-carbon sugar is glucose, galactose, or mannose. The five-carbon sugar is arabinose or xylose. The six-carbon sugar oligomer is sucrose or lactose. Preferably, the sugar is glucose. Alternatively, making a biofuel precursor comprises: (a) providing a feedstock comprising galactose obtained from starch, cellulose, hemicellulose, or pectin; (b) contacting the feedstock of (a) with a biocatalyst that converts the feedstock into a biofuel precursor at: (i) a yield of at least 90% of the yield of the biocatalyst where the feedstock comprises glucose; (ii) a productivity of at least 90% of the productivity of the biocatalyst where the feedstock comprises glucose; and (iii) a titer of at least 90% of the titer of the biocatalyst where the feedstock comprises glucose; and (c) recovering the biofuel precursor. Alternatively, making a biofuel precursor comprises: (a) providing a feedstock comprising mannose obtained from starch, cellulose, hemicellulose, or pectin; (b) contacting the feedstock of (a) with a biocatalyst that converts the feedstock into a biofuel precursor at: (i) a yield of at least 90% of the yield of the biocatalyst, where the feedstock comprises glucose; (ii) a productivity of at least 90% of the productivity of the biocatalyst where the feedstock comprises glucose; and (iii) a titer of at least 90% of the titer of the biocatalyst where the feedstock comprises glucose; and (c) recovering the biofuel precursor. Alternatively, making a biofuel precursor comprises: (a) providing a feedstock comprising xylose obtained from starch, cellulose, hemicellulose, or pectin; (b) contacting the feedstock of (a) with a biocatalyst that converts the feedstock into a biofuel precursor at: (i) a yield of at least 69% of the yield of the biocatalyst, where the feedstock comprises glucose; (ii) a productivity of at least 56% of the productivity of the biocatalyst, where the feedstock comprises glucose; and (iii) a titer of at least 59% of the titer of the biocatalyst where the feedstock comprises glucose; and (c) recovering the biofuel precursor. Alternatively, making a biofuel precursor comprises: (a) providing a feedstock comprising arabinose obtained from starch, cellulose, hemicellulose, or pectin; (b) contacting the feedstock of (a) with a biocatalyst that converts the feedstock into a biofuel precursor at: (i) a yield of at least 56% of the yield of the biocatalyst where the feedstock comprises glucose; (ii) a productivity of at least 70% of the productivity of the biocatalyst where the feedstock comprises glucose; and (iii) a titer of at least 54% of the titer of the biocatalyst where the feedstock comprises glucose; and (c) recovering the biofuel precursor. Alternatively, making a biofuel precursor comprises: (a) providing a feedstock comprising lactose; (b) contacting the feedstock of (a) with a biocatalyst that converts the feedstock into a biofuel precursor at: (i) a productivity of at least 90% of the productivity of the biocatalyst where the feedstock comprises glucose; and (ii) a titer of at least 90% of the titer of the biocatalyst where the feedstock comprises glucose; and (c) recovering the biofuel precursor. Alternatively, making a biofuel precursor comprises: (a) providing a feedstock comprising sucrose; (b) contacting the feedstock of (a) with a biocatalyst that converts the feedstock into a biofuel precursor at: (i) a productivity of at least 50% of the productivity of the biocatalyst where the feedstock comprises glucose; and (ii) a titer of at least 50% of the titer of the biocatalyst where the feedstock comprises glucose; and (c) recovering the biofuel precursor. Alternatively, making a biofuel precursor comprises: (a) providing a feedstock comprising a six carbon sugar obtained from starch, cellulose, hemicellulose, or pectin; (b) contacting the feedstock of (a) with a biocatalyst that converts the feedstock into a biofuel precursor at: (i) a yield of at least 90% of the yield of the biocatalyst where the feedstock comprises glucose; (ii) a productivity of at least 90% of the productivity of the biocatalyst where the feedstock comprises glucose; and (iii) a titer of at least 90% of the titer of the biocatalyst where the feedstock comprises glucose; and (c) recovering the biofuel precursor. Alternatively, making a biofuel precursor comprises: (a) providing a feedstock comprising a five carbon sugar obtained from starch, cellulose, hemicellulose, or pectin; (b) contacting the feedstock of (a) with a biocatalyst that converts the feedstock into a biofuel precursor at: (i) a yield of at least 55% of the yield of the biocatalyst where the feedstock comprises glucose; (ii) a productivity of at least 55% of the productivity of the biocatalyst where the feedstock comprises glucose; and (iii) a titer of at least 55% of the titer of the biocatalyst where the feedstock comprises glucose; and (c) recovering the biofuel precursor. Producing a biofuel precursor comprises contacting a feedstock with the biocatalyst under fermentation conditions suitable for producing a biofuel precursor. Preferred Biocatalyst: The parental microorganism is SA237. The isolated or recombinant biocatalyst comprises a genotype of Escherichia coli BW25113, and further comprising a genotype of: Delta ldhA-fnr::FRT, Delta adhE::FRT, Delta frd::FRT, Delta pta::FRT, pflB::FRT, Delta mdh::FRT, Delta aceF::FRT F'(laclq+), pSA55, pSA69, where the isolated or recombinant biocatalyst produces isobutanol from a carbon source. The biocatalyst is GEVO1530, pSA55, or pSA69. Preferred Nucleic Acid: The nucleic acid is pGV1609, pGV1655, pGV1698, pGV1745, EXAMPLE - No suitable example given.