Y. Tamaru et al., CLONING, DNA-SEQUENCING, AND EXPRESSION OF THE BETA-1,4-MANNANASE GENE FROM A MARINE BACTERIUM, VIBRIO SP STRAIN MA-138, Journal of fermentation and bioengineering, 83(2), 1997, pp. 201-205
The manA gene encoding an extracellular beta-1,4-mannanase of a marine
bacterium, Vibrio sp. strain MA-138, was cloned and sequenced. The ma
nA gene consists of an open reading frame of 1185 nucleotides encoding
a protein of 395 amino acids with a molecular weight of 43,097. A put
ative ribosome-binding site and a promoter region were identified in t
he DNA sequence. ManA of Vibrio sp. strain MA-138 was classified into
family 5 of the glycosyl hydrolases and is highly homologous to the Ma
nAs of Caldocellum saccharolyticum (sequence identity: 53%) and Strept
omyces lividans (sequence identity: 51%). The N-terminal amino acid se
quence of the recombinant enzyme was completely in agreement with that
deduced from the nucleotide sequence and that of the enzyme purified
from strain MA-138. Although the molecular weight of the recombinant M
anA was smaller than that of the enzyme from strain MA-138 on SDS-poly
acrylamide gel electrophoresis, this was attributed to linkage of the
carbohydrate chain to the latter protein. The enzymatic properties of
the recombinant ManA was similar to those of the enzyme from strain MA
-138.