Germ tube

Fig. 2.7 Germ tube formation by Candida albicans. For simplicity the diagram merely illustrates the nuclear content of the parental yeast cell and the developing germ tube. In real life there is a complex rearrangement of cytoplasmic constituents which results in all parts except the apex becoming highly vacuolated.

The patient is started on fluconazole 400 mg/day, but 3 days later has persistent fever and develops hypotension and decreased urine output. Blood cultures reveal a germ tube-negative yeast growing in the blood. Laboratory studies revealed a white blood cell count of 12,300/mm3 (12x109/L), aspartate aminotransferase 68 IU/L (1.13 pKat/L), alanine aminotransferase 75 IU/L (1.25 pKat/L), alkaline phosphatase 168 IU/L (2.8 pKat/L), and normal bilirubin. Serum creatinine is 1.8 mg/dL (159 pmol/L). 

The biochemical similarities of leaf and stem rust elicitors, the missing gene specificity of both elicitors, the fact that an equally active elicitor was isolated from germ tube cell walls of oat crown rust (60), together with the described reactions of different non-hosts to the stem rust elicitor led us to speculate that the isolated elicitors may play a role in the induction of general mechanisms of non-host resistance (130). Although they may be involved in the elicitation of race-cultivar specific resistance as well, race-cultivar specificity in the wheat-stem rust system clearly cannot be explained on the basis of the specificity of the isolated elicitors. One possible explanation would be the occurrence of race-cultivar specific suppressors of the resistance reaction (124,131,132). 

Flavonoids are not always essential signal molecules in mycorrhizal symbioses, however various other phenolic acids can elicit similar effects. " Compounds that actively promote the growth of AMF (i.e., kaempferol, quercetin, and myricetin) " are also required for pollen germination and growth of the germ tube. " " Thus, these compounds may have some general effect on cell elongation.It has been concluded that flavonoids stimulate, but are not essential for mycorrhiza formation. 

Higgins, V.J., The effect of some pterocarpanoid phytoalexins on germ tube elongation of Stem-phylium botryosum. Phytopathology, 78, 339, 1978. 

The dicarboximides inhibit spore germination and cause increased branching, swelling and lysis of germ tubes and hyphal tips. Effects on cell division have been reported but no major inhibition of nucleic acid metabolism, respiration, protein or lipid synthesis has been observed. 

Systemic fungicide, absorbed through roots and green tissues, with translocation acropetally. Acts by inhibiting development of the germ tubes, the formation of appressoria and the growth of mycelia... 

Germ tubes of Puccinia graminis tritici wheat plants (not in culture) lipoxygenase (45)... 

---