Chitinases from uncultured marine microorganisms

Journal Article · Tue Jun 01 04:00:00 EDT 1999 · Applied and Environmental Microbiology

OSTI ID:354328

Cottrell, M T; Moore, J A; Kirchman, D L ^[1]

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1. Univ. of Delaware, Lewes, DE (United States). Coll. of Marine Studies

An understanding of the degradation of organic matter will benefit from a greater appreciation for the genes encoding enzymes involved in the hydrolysis of biopolymers such as chitin, one of the most abundant polymers in nature. To isolate representative and abundant chitinase genes from uncultivated marine bacteria, the authors constructed libraries of genomic DNA isolated from coastal and estuarine waters. The libraries were screened for genes encoding proteins that hydrolyze a fluorogenic analogue of chitin, 4-methylumbelliferyl {beta}-D-N,N{prime}-diacetylchitobioside (MUF-diNAG). The abundance of clones capable of MUF-diNAG hydrolysis was higher in the library constructed with DNA from the estuary than in that constructed with DNA from coastal waters, although the abundance of positive clones was also dependent on the method used to screen the library. Plaque assays revealed nine MUF-diNAG-positive clones of 75,000 screened for the estuarine sample and two clones of 750,000 for the coastal sample. A microtiter plate assay revealed approximately 1 positive clone for every 500 clones screened in the coastal library. The number of clones detected with the plaque assay was consistent with estimates of the portion of culturable bacteria that degrade chitin. Their results suggest that culture-dependent methods do not greatly underestimate the portion of marine bacterial communities capable of chitin degradation.

• Sponsoring Organization: USDOE, Washington, DC (United States)
• OSTI ID: 354328
• Journal Information: Applied and Environmental Microbiology, Journal Name: Applied and Environmental Microbiology Journal Issue: 6 Vol. 65; ISSN AEMIDF; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
BACTERIA
CELLULASE
CHITIN
DNA
DNA-CLONING
GENES
METABOLISM
SEAWATER