Biology Reference
In-Depth Information
(A)
(B)
Figure 3:
Type IV pili
of Synechocystis
sp. strain PCC 6803. Pictures kind courtesy of Professor D. Dienst, Humboldt University
Berlin, Institute of Biology/Plant Biochemistry, Chausseestr. 117, 10115 Berlin/Germany.
mutational analysis of genes governing pilus biogenesis, motility and transformation, a number of
workers identifi ed their role. Okamoto and Ohmori (1999) presented evidences for the requirement
of
pilT
/
pilC
gene cluster for motility and transformation competency in
Synechocystis
sp. strain PCC
6803. The role of an alternative sigma factor (SigF) in motility and pilus formation in
Synechocystis
sp.
strain PCC 6803 was studied by Bhaya
et al
. (1999). Mutation of SigF conferred a pleiotropic effect on
the cells such as (i) accumulation of extracellular pigments and proteins, (ii) the loss of pili leading
to loss of motility and so phototaxis and (iii) a signifi cant reduction in the levels of mRNA of
pilA1
