SUMMARY: Spores of Bacillus subtilis 1604 can be induced to germinate by incubation in L-Ala (the ALA pathway) or in a combination of β-D-gIucose (Glc), β-fructose (Fru), L-Asn and K+ (the GFAK pathway). Biochemical analysis of the germination response of a gerA mutant deficient in the ALA pathway revealed that L-Ala can replace L-Asn in the GFAK pathway (the GFAlaK pathway). In contrast to the ALA pathway of both the wild-type and of a gerB mutant, the GFAlaK pathway w as insensitive to D-Ala and showed the same overall inhibitor profile as the GFAK pathway of wild-type and gerA spores. It is deduced that a second L-Ala receptor with different characteristics to that functioning in the ALA pathway is present in wild-type spores. Analysis of the germination response of a gerB mutant showed that whilst the rate of ALA germination could be stimulated by Glc as well as by Fru in the presence of Glc, the spores could not germinate in GFAK. In addition, Glc and Fru were unable to reverse D-Ala inhibition of L-Ala germination which they do in the wild-type. Thus, in the gerB mutant, the L-Ala/L-Asn receptor in the GFAK pathway is defective. It is concluded that the germination receptors in the ALA and GFAK pathways can functionally interact with each other to initiate B. subtilis spore germination. This conclusion is discussed in relation to proposed models of triggering of spore germination.
FosterS.J.,
JohnstoneK.1989; The trigger mechanism of bacterial spore germination.. In Regulation of Prokaryotic Development pp. 89–108, Edited by.
SmithI.,
Slepecky R.A.,
SetlowP.
Washington, D.C.:: American Society for Microbiology.;
FreeseE.,
CashelM.1965; Initial stages of germination.. In Spores III pp. 144–151, Edited by.
CampbellL.L.,
HalvorsonH.O.
Ann Arbor, Michigan:: American Society for Microbiology.;
FreeseE.,
FortnagelU.1969; Growth and sporulation of Bacillus subtilis mutants blocked in the pyruvate dehydrogenase complex.. Journal of Bacteriology 99:745–756
IrieR.,
OkamotoT.,
FujitaY.1980; Initiation of germination of Bacillus subtilis spores by allylglycine.. Journal of General and Applied Microbiology 26:425–428
IrieR.,
OkamotoT.,
FujitaY.1982; A germination mutant of Bacillus subtilis deficient in response to glucose.. Journal of General and Applied Microbiology 28:345–354
KandaK.,
YasudaY.,
TochikuboK.1988; Germination-initiating activities for Bacillus spores of analogues of L-alanine derived by modification at the amino or carboxyl group.. Journal of General Microbiology 134:2747–2755
LaffertyE.,
MoirA.1977; Further studies on conditional germination mutants of Bacillus subtilis 168.. In Spore Research 1976 pp. 87–105, Edited by.
BarkerA.N.,
Dring G.J.,
EllarD.J.,
GouldG.W.,
WolfJ.
London:: Academic Press.;
MoirA.,
SmithD.A.1985; The genetics of spore germination in Bacillus subtilis.. In Fundamental and Applied Aspects of Bacterial Spores pp. 89–100, Edited by.
DringG.J.,
EllarD.J.,
GouldG.W.
London:: Academic Press.;
MoirA.,
LaffertyE.,
SmithD.A.1979; Genetic analysis of spore germination mutants of Bacillus subtilis 168 : the correlation of phenotype with map location.. Journal of General Microbiology 111:165–180
RatherP.N.,
MoranC.P.1988; Compartment-specific transcription in Bacillus subtilis : identification of the promoter for gdh.. Journal of Bacteriology 170:5086–5092
SammonsR.L.,
MoirA.,
SmithD.A.1981; Isolation and properties of spore germination mutants of Bacillus subtilis 168 deficient in the initiation of germination.. Journal of General Microbiology 124:229–241
StewartG.S.A.B.,
JohnstoneK.,
HagelbergE.,
EllarD.J.1981; Commitment of bacterial spores to germinate: a measure of the trigger reaction.. Biochemical Journal 198:101–106
VenkatasubramanianP.,
JohnstoneK.1989; Biochemical analysis of the Bacillus subtilis 1604 spore germination response.. Journal of General Microbiology 135:2723–2733
WaxR.,
FreeseE.1968; Initiation of the germination of Bacillus subtilis spores by combination of compounds in place of L-alanine.. Journal of Bacteriology 95:433–438
WaxR.,
FreeseE.,
CashelM.1967; Separation of two functional roles of L-alanine in the initiation of Bacillus subtilis spore germination.. Journal of Bacteriology 94:522–529
WolgamottG.D.,
DurhamN.N.1971; Initiation of spore germination in Bacillus cereus: a proposed allosteric receptor.. Canadian Journal of Microbiology 17:1043–1048
YasudaY.,
TochikuboK.1984; Relation between D-glucose and L-alanine and D-alanine in the initiation of germination of Bacillus subtilis spores.. Microbiology and Immunology 28:197–207
YasudaY.,
TochikuboK.1985; Germination-initiation and inhibitory activities of L-alanine and D-alanine analogs for Bacillus subtilis spores-modification of methyl-group of L-alanine and D-alanine.. Microbiology and Immunology 29:229–241
YasudaY.,
Namiki-KanieS.,
HachisukaY.1978a; Inhibition of germination of Bacillus subtilis spores by alcohols.. In Spores VII pp. 104–108, Edited by.
ChamblissG.,
VaryJ.C.
Washington, D.C.:: American Society for Microbiology.;
YasudaY.,
Namiki-KanieS.,
HachisukaY.1987b; Inhibition of Bacillus subtilis spore germination by various hydrophobic compounds: demonstration of hydrophobic character of the L-alanine receptor site.. Journal of Bacteriology 136:484–490
ZuberiA.R.,
FeaversI.M.,
MoirA.1985; Identification of three complementation units in the gerA spore germination locus of Bacillus subtilis.. Journal of Bacteriology 162:756–762
ZuberiA.R.,
MoirA.,
FeaversI.M.1987; The nucleotide-sequence and gene organization of the gerA spore germination operon of Bacillus subtilis 168.. Gene 51:1–11