Characterization of pectin lyase produced by an endophytic strain isolated from coffee cherries.
OBJECTIVE
The effect of endophytic bacterial activity on the quality of coffee beverage was studied.


RESULTS
A survey of the micro-organisms in coffee cherries was performed before harvesting, and their growth on the main nutrients available in coffee cherries was determined in vitro.


CONCLUSIONS
Many endophytic bacteria were isolated from surface-sterilized coffee cherries. One of the pectinolytic strains was physiologically and phenotypically characterized, and was tentatively identified by partial 16S rDNA sequencing as Paenibacillus amylolyticus. This endophytic strain produced an extracellular pectinase with maximal activity at 40 degrees C and pH 7.9, and was thermostable up to 45 degrees C. EDTA and metal ions had little effect on pectin lyase activity. Km and Vmax values were 4.6 mg ml(-1) and 94.0 10(-8) mol min(-1) ml(-1), respectively.


CONCLUSIONS
Pectin lyases have been found in fungi but rarely in bacteria, and this isolate is a promising tool for regulation studies of these enzymes.
Sakiyama
C C
CC
Departamento de Microbiologia, BIOAGRO, Universidade Federal de Viçosa, MG, Brazil.
Paula
E M
EM
Pereira
P C
PC
Borges
A C
AC
Silva
D O
DO
D001406:Bacillaceae / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification*; D001938:Brazil; D003069:Coffee / Q000378:metabolism / Q000382:microbiology*; D004492:Edetic Acid / Q000494:pharmacology; D004795:Enzyme Stability; D005516:Food Microbiology; D007700:Kinetics; D008670:Metals / Q000494:pharmacology; D010368:Pectins / Q000378:metabolism; D010802:Phylogeny; D011133:Polysaccharide-Lyases / Q000302:isolation & purification* / Q000378:metabolism*; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013242:Sterilization; D013379:Substrate Specificity; D013696:Temperature
D003069:Coffee; D008670:Metals; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D010368:Pectins; D004492:Edetic Acid; D011133:Polysaccharide-Lyases; C027349:pectin lyase