Published Date

June 1991, Volume 22, Issue 6, pp 365-370

First online: 

A study of cornstarch granule digestion by an unusually high molecular weightα-amylase secreted byLactobacillus amylovorus

• Syed H. Imam
• , Anthony Burgess-Cassler
• , Gregory L. Cote
• , Sherald H. Gordon
• , Frederick L. Baker

Abstract

The cells ofLactobacillus amylovorus (NRRL B-4540), grown in a medium containing 2% cornstarch as the sole carbon source, secreted an amylase activity that rapidly solubilized cornstarch. Fourier transform infrared (FTIR) spectroscopic analyses showed that 80–90% of starch was consumed by bacteria in a 10-day-old culture medium. The remnant of starch granules digested in the culture medium inoculated with the cells ofL. amylovorushave also lost their characteristic iodine-binding capacity as visualized by starch dye-binding microplate assay and light microscopy. Scanning electron miscroscopy (SEM) of granules from a 48-h culture medium showed hollow and fragmented granules with a pitting phenomenon characteristically produced byα-amylase activity. Analysis of an enzyme preparation from a culture medium ofL. amylovorus revealed that the putative enzyme appears to be a single protein band of unusually high Mr (150,000) on SDS gels stained for amylase activity. Analysis of starch digestion products by thin layer chromatography (TLC) showed enzyme activity typical ofα-amylase.

References

1. 1.
   Anderson KL, Salyers AA (1989) Biochemical evidence that starch breakdown byBacteroides thetaiotaomicroninvolves outer membrane starch-binding sites and periplasmic starch-degrading enzymes. J Bacteriol 171:3192–3298
2. 2.
   Burgess-Cassler A, Imam SH, Gould JM (1991) High molecular weight amylase activities from bacteria degrading starchplastic film. Appl Environ Microbiol 57:612–614
3. 3.
   Fitt LE, Snyder EM (1984) Photomicrographs of starches. In: Whistler J, Bemiller N, Pascall EF (eds) Starch: chemistry and technology, 2nd ed. New York: Academic Press, pp 675–689
4. 4.
   Gallant D, Mercier C, Guilbot A (1972) Electron microscopy of starch granules modified by bacterial amylases. Cereal Chem 49:354–365
5. 5.
   Giulian GG, Moss RL, Greaser M (1983) Improved methodology for analysis and quantitation of proteins of one-dimensional silver-stained slab gel. Anal Biochem 129:277–287
6. 6.
   Goldner WR, Boyer CD (1989) Starch-granule-bound proteins and polypeptides: The influence of the waxy mutations. Starch/Stärke 41:250–254
7. 7.
   Gould JM, Gordon SH, Dexter LB, Swanson CL (1990) Biodegradation of starch-containing plastics. In: Glass JE, Swift G (eds) Agricultural and synthetic polymers: biodegradability and utilization. ACS Symposium series No 433. Washington, DC: American Chemical Society, pp 65–75
8. 8.
   Greenwell P, Schofield JD (1986) A starch granule protein associated with endoplasmic endosperm softness in wheat. Cereal Chem 63:379–380
9. 9.
   Imam SH (1989) A tightly bound Mr 55000 polypeptide in cornstarch associated with the amylose portion of the granule. J Cereal Sci 9:231–236
10. 10.
    Imam SH, Gould JM (1990) Adhesion of an amylolyticArthrobacter sp. to starch-containing plastic films. Appl Environ Microbiol 56:872–876
11. 11.
    Imam SH, Greene RV, Griffin HL (1990) Adhesive properties of a symbiotic bacterium from a wood-boring marine shipworm. Appl Environ Microbiol 57:1317–1322
12. 12.
    Koch VH, Ropper H (1989) New industrial products from starch. Starch/Stärke 40:121–131
13. 13.
    Lacks SA, Springhorn SS (1980) Renaturation of enzyme after polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. J Biol Chem 255:7467–7473
14. 14.
    Laemmli UK (1970) Cleavage of structural proteins during the assembly of the head of the bacteriophage T4. Nature (London) 227:680–685
15. 15.
    Nakamura LK (1981)Lactobacillus amylovorus, a new starch-hydrolyzing species from cattle waste-corn fermentations. Int J Syst Bacteriol 31:56–63
16. 16.
    Robyt JF (1984) Enzyme in the hydrolysis and synthesis of starch. In: Whistler J, BeMiller N, Pascall EF (eds) Starch: chemistry and technology, 2nd ed. New York: Academic Press, pp 87–122
17. 17.
    Robyt JF, White BJ (1987) Chromatographic techniques. In: Robyt JF, White BJ (eds) Biochemical techniques: theory and practice. Brooks, California: Cole Publ Company, pp 107–109
18. 18.
    Roper H, Koch VH (1988) New carbohydrate derivatives from biotechnical and chemical processes. Starch/Stärke 40:453–464
19. 19.
    Shogren RL, Thompson AR, Greene RV, Gordon SH, Cote G (1991) Polymer compatibility and biodegradation of starchpoly(ethylene-co-acrylic acid)-polyethylene blends. J Appl Polymer Sci, “in press”
20. 20.
    Tremoto Y, Kira I, Hayashida S (1989) Multiplicity and preferential inactivation by proteolysis as to raw starch-digestibility of bacterialα-amylases. Agric Biol Chem 53:601–605
21. 21.
    Tsan-Piao, Spilatro SR, Preiss J (1988) Subcellular localization of amylases inArabidopsis leaf. Plant Physiol 86:251–259
22. 22.
    Vihinen M, Mäntsälä P (1989) Microbial amylolytic enzymes. Crit Rev Biochem Mol Biol 24:329–418

For further details log on website :
http://link.springer.com/article/10.1007%2FBF02092156