A steam steriliser is used to sterilise liquid medium for fermentation. The initial concentration of contaminating organisms is 10⁸ per litre. For design purposes, the final acceptable level of contamination is usually taken to be 10^-3cells; this corresponds to a risk that one batch in a thousand will remain contaminated even after the sterilisation process is complete. For how long should 1 m³ medium be treated if the temperature is 121⁰C ________________.

 To be safe, assume that the contaminants present are spores of Bacillus stearothermophilus, one of the most heat-resistant microorganisms known. For these spores the activation energy for thermal death is 283 kJ gmo1^-1 and the Arrhenius constant is 10^36.2 s^-1

TLS Online TPP Program

#Question id: 15137

#Section 6: Plant, Animal and Microbial Biotechnology

Most mitochondrial proteins however, are manufactured under the direction of the nucleus. Mitochondria reproduce by 

TLS Online TPP Program

#Question id: 15138

#Section 7: Recombinant DNA technology and Other Tools in Biotechnology

Match the items in group 1 with an appropriate description in group 2.

Group 1	Group 2
(P) SWISS PROT	(1) derived protein structure database
(Q) Local alignment	(2) protein sequence database
(R) CATH	(3) GAP
(S) Global alignment	(4) Smith–Waterman algorithm

TLS Online TPP Program

#Question id: 15139

#Section 7: Recombinant DNA technology and Other Tools in Biotechnology

Which one of the following is NOT a structure or structurally derived database?

TLS Online TPP Program

#Question id: 15140

#Section 7: Recombinant DNA technology and Other Tools in Biotechnology

Two types of pair-wise sequence alignment of the same hypothetical protein sequence fragments are illustrated in the figure below. Vertical bars between the sequences indicate the presence of identical amino acids. * symbols in Figure Y indicate residues not included in the alignment.

Which one of the following is correct?

TLS Online TPP Program

#Question id: 15141

#Section 7: Recombinant DNA technology and Other Tools in Biotechnology

An alignment of two protein sequences is given below:

Sequence A         A G A A C D E V I G

Sequence B         A G E Y C D A V I G

The similarity score (%) for the above alignment will be:

TLS Online TPP Program

#Question id: 15142

#Section 7: Recombinant DNA technology and Other Tools in Biotechnology

Dot matrix analysis of the amino acid sequences of lambda phage cI (horizontal sequence) and phage P22 c2 (vertical sequence) repressors is shown below. Which one of the following is correct?