132 research outputs found
Is “Wolf‐Pack” Predation by Antimicrobial Bacteria Cooperative?:Cell Behaviour and Predatory Mechanisms Indicate Profound Selfishness, Even when Working Alongside Kin
CELL DEATH DURING FRUITING BODY FORMATION IN MYXococcus
Massive cell death occurs during fruiting construction by several species
of Myxococcus . The events which occur lead us to the hypothesis that
regulated senescence and cell death are integral part of myxobacterial
development. During fruiting body formation by M. xanthus 60 - 8) % of
the vegetative cells lyse. The majority of the survivina cells are eventually
converted to myxospores in the fruiting body. This lysis has been
measured both by the loss of 3y-methy1 thymidine label from DHA of the
cells and by actual cell counts. Such lysis occurs under a variety of
conditions leading to fruiting body formation. We have also demonstrated
lysis during fruiting body formation in Myxococcus fulvus and Myxococcus
virescens.
If cells are removed at various times during fruiting body formation and
replaced in a liquid growth medium the tendency to lyse is reversible
until the fruiting bodies have formed; at that time the vegetative cells
become irreversibly committed to lysis.
We suggest that lysis in the organisms we have examined is a functional
and necessary part of the developmental cycle. It is possible that the
lysing cells are providing a source of biosynthetic precursors and/or
a source of energy for the formation of myxospores and/or fruitina
bodies
A stochastic model of the logistics actions required to ensure the availability of spare parts during maintenance of railway vehicles
Phylogeny of mercury resistance (mer) operons of gram-negative bacteria isolated from the fecal flora of primates
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