Abstract: An improved method of mutanting DNA is provided comprising mutating a gene bearing phagemid in a host and infecting the host cell with a suitable helper phage to initiate packaging of the DNA into a phagemid. The packaged phagemid is then used to infect a second host cell. The method facilitates more efficient screening for genetic diversity. Also, the gene of interest is mutated and separable from the host cell which undergoes the mutational event reducing false positive results or other artifacts of general mutation techniques.

Abstract: The invention relates to a heat-stable pullulanase having the property of hydrolysing glucosidic bonds of the .alpha.-1,6 type in amylopectin and having an enzymatic activity in an acid medium and at a temperature of about 60.degree. C.The invention also relates to strains of microorganisms which produce this pullulanase and processes for the preparation of this pullulanase.The invention also relates to the uses thereof and compositions comprising the product.The invention also relates to a DNA molecule. The invention relates to an expression vector containing this DNA molecule and to a chromosomal integration vector containing this DNA molecule.

Abstract: An enzymatic system comprised of glucose oxidase and a catalase of the same or different sources to result in the complete conversion of glucose to gluconic acid at a glucose concentration greater than 25% (w/w) ds. The resultant gluconic acid, which is essentially free from impurities normally associated with the fermentation process, is then spray granulated to produce a low-dust dry product.