P. syringae pv. Syringae (Pss) secrete syringolin A (SylA), a peptide derivative synthesized by a mixed nonribosomal peptide synthetase/polyketide synthetase encoded by a gene cluster. 

TLS Online TPP Program

#Id: 8322

#XL - Q Biochemistry

Steady-state phase

G-actin monomers exchange with subunits at the filament ends, but there is no net change in the total length of filaments.

TLS Online TPP Program

#Id: 8321

#XL - Q Biochemistry

Elongation phase

short oligomer rapidly increases in length by the addition of actin monomers to both of its ends, causing filament elongation

TLS Online TPP Program

#Id: 8320

#XL - Q Biochemistry

The lag phase can be reduced or abolished entirely by adding premade nuclei.

TLS Online TPP Program

#Id: 8319

#XL - Q Biochemistry

Nucleation phase 

Lag period (Time taken for nucleation) Rate-limiting Step.

TLS Online TPP Program

#Id: 8318

#XL - Q Biochemistry

Nucleation phase 

Two G-actin molecules bind relatively weakly to each other, but addition of a third actin monomer to form a trimer makes the entire group more stable, acts as a nucleus for polymerization.

TLS Online TPP Program

#Id: 8317

#XL - Q Biochemistry

Actin polymerization in vitro proceeds in three steps:

1.Nucleation phase

2.Elongation phase

3.Steady-state