You are carrying out PCRs in lab. Why do you not need helicase, SSB, primase, ligase, sliding clamp? Solution 1. Helicase: Helicase is an eznyme that plays a crucial role in seperating the DNA double helix by unwinding it. 2. SSB: It stands for Single-Stranded DNA Binding Protein (SSB). It binds with high affinity to single-stranded DNA and destabilizes helical duplexes. This helps DNA polymerases to bind to substrates easily. SSB do not bind to double stranded DNAs. 3. Primase: Primase is an enzyme that synthesize primers (short stretches of DNA for the DNA synthesis to proceed) in vivo. In In a PCR experiment, two specific primers are designed and added in the reaction for amplifying specific sequences. 4. Ligase: This enzyme catalyze the DNA repair process by joining of ends of DNA molecules. In these reactions, this enzyme links the phosphate to a neighboring sugar molecule, thus forming the backbone of DNA. 5. Sliding clamp: This clamp protein binds to DNA polymerase (enyme synthesizing the DNA chain), and prevents it from dissociation from the template. Thus it acts as a promoting factor in DNA replication process. The clamp-polymerase interactions are stronger and more specific. It increases the rate of reaction progression..