NURSING ANM AND GNM

Detailed explanation-1: -Purified bacterial signal molecules, the nodulation factors (NFs), which are lipochitooligosaccharides, induce root hair deformation in the appropriate host legume and have been proposed to be a key player in eliciting root hair curling.

Detailed explanation-2: -The nod genes are the key bacterial determinants of the signal exchange between the two symbiotic partners. The product of the nodD gene is a transcriptional activator protein that functions as receptor for a flavonoid plant compound.

Detailed explanation-3: -The common nodABC genes, present in all Rhizobium species, are required for the synthesis of the core structure of NFs. NodC is an N-acetylglucosaminyltransferase, and NodB is a chitooligosaccharide deacetylase; NodA is involved in N-acylation of the aminosugar backbone.

Detailed explanation-4: -nod genes regulate the infection and nodulation process. a. nod gene expression is induced by flavonoids produced by the plant. b. nod genes A, B, and C are involved in synthesis of a lipooligosaccharide signaling molecule that induces the formation of the infection thread and root cortical cell divisions.

Detailed explanation-5: -Chemically, the Nod factors (NFs) are lipochitooligosaccharides, produced mainly by bacteria of the Rhizobium genus. They are the main signaling molecules involved in the initiation of symbiosis between rhizobia and legume plants. Nod factors affect plant tissues at very low concentrations, even as low as 10-12 mol/L.