Method for screening microorganisms for the production of amylolytic enzymes

DETAILED DESCRIPTION OF THE INVENTION One criterion of strain improvement is a change in the activity and/or amount of a particular enzyme produced by an organism.
In general a screening procedure is employed whereby each candidate is tested for the desired change in the activity and/or amount of the enzyme.
However, when evaluating a large population of potential candidates, as would be the case when attempting to isolate a new strain from nature, a screening system alone may be highly labor intensive and expensive.
In such situations it would be highly desirable to reduce the initial population of candidates by selecting therefrom a sub-population whose members would most likely display the desired trait upon subsequent screening.
As has been noted above, particularly useful microorganisms for the production of heat-stable .
alpha.
-amylase are members of the species Bacillus licheniformis.
It is a preferred embodiment of the instant invention, therefore, to provide a means whereby members of the species Bacillus licheniformis are present among a sub-population of organisms to be screened for the presence of .
alpha.
-amylase activity, the sub-population having been selected from a larger population of organisms based upon a property other than the ability to produce .
alpha.
-amylase.
A particular valuable finding, in light of the subject invention, has been the demonstration that members of the species Bacillus licheniformis are facultative anaerobes.
This ability to grow in the absence of oxygen distinguishes from most other amylase producing Bacilli, such as Bacillus subtilis, and provides the bases of a quite stringent selection system.
Thus, according to one embodiment, a soil sample is inoculated onto a solid medium which promotes the growth of a microorganism and the synthesis of .
alpha.
-amylase thereby.
The plates are incubated under anaerobic conditions thus eliminating any strict aerobic organisms.
The surviving organisms will be of two classes: strict anaerobes, those which will grow only under anaerobic conditions and facultative anaerobes those which will grow under both aerobic and anaerobic conditions