Category:Team Blue A

"In any case, a scrambled 24 residue peptide with the same amino acid composition (Figure 1(c)) was without effect on in vitropackaging by the same assay, thereby providing evidence, at least with the unpolymerized peptide, that the packaging inhibition observed was specific and dependent upon the gp20 peptide sequence"

Different amounts of PolyPs were added in chains in the medium containing the PPX2His (exopolyphosphatase with a His tag) to see if an increase in the length of the PolyP chain increased the activity if the PPX2 activity. According to the results in Figure 3, the increase in the length (from short to medium) increased the percent of activity. Therefore, the enzyme activity depends on the amount of cellular PolyP available.

Figure 3 demonstrates "Arrowheads show the mature DNA produced upon complementation with the sizX allele (1), mature DNA resulting from background effects under our experimental conditions (see text) (2), DNA packaged in presence of gp6 mutant forms that caused a low efficiency phenotype (3), and DNA packaged in presence of a gp6Siz mutant protein (4)."

Table 2 demonstrates gp6 single amino acid substitutions affecting the packaging of sizX chromosome.

The deletion of ppx1 and ppx2 in C. glutamicum resulted in the decrease of exopolyphosphatase activity. Figure 1 shows that there was an accumulation of cellular PolyP mutated C. glutamicum cells versus wild type. This shows that the exopolyphosphatase protein serves as a regulatory protein of cellular PolyP

McsB play a role in regulating transcription of CtsR-dependent heat shock genes. Figure 5- In the mcsB mutants, CtsR-dependent heat shock proteins under non-stressed conditions were increased when compared with the wild-type. McsB influences the CtsR-mediated repression negatively. Figure 6B- The half-life of the CtsR repressor was increased in McsB mutants, suggesting that McsB destabilizes CtsR.

Through gel mobility shift experiments (Figure 6, lanes 8-10), it was shown that addition of McsB to CtsR led to a decrease in the amount of DNA retarded by CtsR. This suests that McsB can remove the DNA binding capacity of CtsR.

McsA play a role in regulating transcription of CtsR-dependent heat shock genes. Figure 5- In the mcsA mutants, CtsR-dependent heat shock proteins under non-stressed conditions were increased when compared with the wild-type.

Figure 6B- In nonstressed McsA mutant cells, the CtsR level was lower than it was in the wild type. After heat shock, CtsR levels in the mutant decreased suggestin that CtsR is less stable without McsA. The half-life of CtsR was also lower in cells lacking McsA

Through gel mobility shift experiments (Figure 6), it was shown that addition of McsA does not influence he CtsR DNA binding activity while excess (12-fold) McsA could promote CtsR-dependent DNA binding.

"In this model one full 3600 rotation of the portal protein corresponds to inserting 65 bp of dsDNA at the expense of a minimum of 32.5 ATPs, if it is assumed that each equivalent unitary interaction between the two structures is coupled to one ATP hydrolysis reaction and leads to the translocation of 2 bp (Figure 3d-e). Furthermore, the model predicts (Figure 4) that the portal protein subunits are activated in the order: 1, 4, 7, 10, 13, 3, 6, 9, 12, 2, 5, 8, 11, 1, etc., thereby equally employing all subunits of the portal structure during the translocation process."

The enzymes were not found to exist as monomers in equilibrium or while unfolding. This suggests that the protein is extremely stable throughout experimental temperatures from 5-70 degrees Celsius with a maximum stability at about 35 degrees C.

With an E value of 1e-14, there is strong support for sequence similarity (accession #: WP_010865375.1).

The enzyme does not show much structural changes when bound to its coenzyme NADPH and its inhibitor methotrexate. The enzyme also forms a homodimer, which contributes to its extreme stability.

Typically, dihydrofolate reductase (DHFR) catalyzes the NADPH-dependent reduction of dihydrofolate (DHF) to tetrahydrofolate (THF). DHFR acts in a catalytic cycle of 5 different intermediates. In the mutant (by changing Leu 28 to Phe), the dissociation rate of the enzyme:substrate complex increases by 10-20 fold. In addition, the rates of the exchange of the excited closed states are very different in the mutants, despite the similarities found in the ground states of the mutant and wild-types. There are 2 pathways, intrinsic and allosteric pathways that this enzyme can take depending on the environmental conditions.

Transfer annotation from gene page ECOLI:DYR.

With an E value of 2e-35, there is strong support for sequence similarity (accession #: 5CC9_A).

Transfer annotation from gene page LACCA:DYR.

Strong sequence similarity with an E value of 2E-34. Accession #: 4DFR_A

Using crystallography, scientists determined that when NADPH binds to dihydrofolate reductase, the enzyme:substrate complex geometry stands out. Nicotinamide interacts with 3 oxygen atoms and 3 hydrogen atoms in this very polar environment.