Some Cyanobacteria synthesize semi-amylopectin type alpha-polyglucans instead of glycogen.
It is widely accepted that green plants evolved the capacity to synthesize the highly organized branched alpha-polyglucan amylopectin with tandem-cluster structure, whereas animals and bacteria continued to produce random branched glycogen. Although most previous studies documented that cyanobacteria accumulate glycogen, the present study shows explicitly that some cyanobacteria such as Cyanobacterium sp. MBIC10216, Myxosarcina burmensis and Synechococcus sp. BG043511 had distinct alpha-polyglucans, which were designated as semi-amylopectin. The semi-amylopectin was intermediate between rice amylopectin and typical cyanobacterial glycogen in terms of chain length distribution, molecular size and length of the most abundant alpha-1,4-chain. It was also found that Cyanobacterium sp. MBIC10216 had no amylose-type component in its alpha-polyglucans. The evolutionary aspect of the structure of alpha-polyglucan is discussed in relation to the phylogenetic evolutionary tree of 16S rRNA sequences of cyanobacteria.
Nakamura
Yasunori
Y
Faculty of Bioresource Sciences, Akita Prefectural University, Akita-City, 010-0195 Japan. nakayn@akita-pu.ac.jp
Takahashi
Jun-Ichiro
J
Sakurai
Aya
A
Inaba
Yumiko
Y
Suzuki
Eiji
E
Nihei
Satoko
S
Fujiwara
Shoko
S
Tsuzuki
Mikio
M
Miyashita
Hideaki
H
Ikemoto
Hisato
H
Kawachi
Masanobu
M
Sekiguchi
Hiroshi
H
Kurano
Norihide
N
D000687:Amylopectin / Q000096:biosynthesis* / Q000737:chemistry; D000688:Amylose / Q000737:chemistry; D000458:Cyanobacteria / Q000378:metabolism*; D019143:Evolution, Molecular; D005936:Glucans / Q000096:biosynthesis* / Q000737:chemistry; D006003:Glycogen / Q000096:biosynthesis* / Q000737:chemistry; D015394:Molecular Structure; D008970:Molecular Weight; D012275:Oryza / Q000378:metabolism; D010802:Phylogeny; D012335:RNA, Ribosomal / Q000235:genetics
D005936:Glucans; D012335:RNA, Ribosomal; D006003:Glycogen; D000688:Amylose; D000687:Amylopectin