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T D Ingolia

Publications and source records attributed to T D Ingolia.

21 records · Page 2Linked to original sources

Response to a metal ion-citrate complex in bacterial sensing.

Salmonella typhimurium responds chemotactically to gradients of divalent cations in the presence of citrate ions. The actual chemoeffector is the citrate-metal ion complex, which acts as an attractant. Citrate (which is also a chemoeffector for Salmonella) and the citrate-metal ion complex are recognized by different receptors. The response of Salmonells, which can transport citrate through its membrane, is quite different than that of Escherichia coli, which cannot.

Bacteria↗

The role of calcium in fusion of artificial vesicles.

Small phospholipid vesicles (liposomes) fuse upon calcium addition as demonstrated by electron microscopy, light absorbance increases, and mixing of original liposome contents within the boundaries of the fused liposome. The integrity of the fusion event is demonstrated by a novel assay based on the luminescence of firefly extract when mixed with ATP. Subsequent addition of valinomycin or the calcium ionophore A23187 leads to further fusion as shown by electron microscopy, light microscopy, and additional absorbance increase. Concomitant with this second absorbance increase is an increase in the amount of calcium that associates with the liposomes. This increased calcium association is more than can be accounted for by equilibration of 5 mM Ca2+ across the membrane and must indicate exposure of extra calcium binding sites. Binding of calcium to the inner side of the membrane may catalyze the second stage of liposome fusion.

Adenosine Triphosphate↗