%PDF-1.3 1 0 obj << /Type /Catalog /Outlines 2 0 R /Pages 3 0 R >> endobj 2 0 obj << /Type /Outlines /Count 0 >> endobj 3 0 obj << /Type /Pages /Kids [6 0 R ] /Count 1 /Resources << /ProcSet 4 0 R /Font << /F1 8 0 R /F2 9 0 R /F3 10 0 R /F4 11 0 R >> /XObject << /I1 16 0 R /I2 17 0 R >> >> /MediaBox [0.000 0.000 612.000 792.000] >> endobj 4 0 obj [/PDF /Text /ImageC ] endobj 5 0 obj << /Creator (DOMPDF) /CreationDate (D:20180524061537+00'00') /ModDate (D:20180524061537+00'00') /Title (Report 05-2018) >> endobj 6 0 obj << /Type /Page /Parent 3 0 R /Annots [ 12 0 R 14 0 R ] /Contents 7 0 R >> endobj 7 0 obj << /Length 5407 >> stream 1.000 1.000 1.000 rg 45.266 232.854 521.469 513.880 re f 0.773 0.773 0.773 RG 0.75 w 0 J [ ] 0 d 45.641 233.229 520.719 513.130 re S 0.773 0.773 0.773 rg 61.016 248.604 m 550.984 248.604 l 550.984 249.354 l 61.016 249.354 l f 0.000 0.000 0.000 rg BT 61.016 695.342 Td /F1 13.5 Tf [(One thing we have learnt this week plastic breakdown)] TJ ET 0.400 0.400 0.400 rg BT 61.016 666.755 Td /F2 9.0 Tf [(Posted on )] TJ ET BT 104.045 666.755 Td /F3 9.0 Tf [(April 20,2018)] TJ ET BT 159.575 666.755 Td /F2 9.0 Tf [( by )] TJ ET BT 174.083 666.755 Td /F3 9.0 Tf [(admin)] TJ ET 0.000 0.000 0.000 rg BT 61.016 639.266 Td /F4 9.0 Tf [(You can hardly move at the moment for news of plastic and its role in the environment. As we have learnt plastic )] TJ ET BT 61.016 628.277 Td /F4 9.0 Tf [(breakdown is a really huge problem. Could a group of )] TJ ET 0.000 0.000 0.800 rg BT 279.617 628.277 Td /F4 9.0 Tf [(researchers)] TJ ET 0.000 0.000 0.800 RG 0.18 w 0 J [ ] 0 d 279.617 627.125 m 327.128 627.125 l S 0.000 0.000 0.000 rg BT 327.128 628.277 Td /F4 9.0 Tf [( discovered a way of breaking down one very )] TJ ET BT 61.016 617.288 Td /F4 9.0 Tf [(commonly used plastics? Poly\(ethylene terephthalate\) \(PET\) is a very common plastic used to make drink bottles and )] TJ ET BT 61.016 606.299 Td /F4 9.0 Tf [(other materials such as clothes. Its structure is shown below. Its a polymer with thousands of the repeating units. )] TJ ET q 162.000 0 0 83.250 61.016 520.851 cm /I2 Do Q BT 223.016 537.501 Td /F4 9.0 Tf [(A group in Japan discovered a new bacterium in waste recycling centre that could )] TJ ET BT 61.016 512.060 Td /F4 9.0 Tf [(use PET as its main energy and carbon source. Bacteria need both of these and they do not have to be the same thing. )] TJ ET BT 61.016 501.071 Td /F4 9.0 Tf [(Simple sugars such as glucose provide both in one molecule but sometimes the energy source \(which is basically )] TJ ET BT 61.016 490.082 Td /F4 9.0 Tf [(electrons\) can be provided by inorganic molecules. It makes it simpler that the organism uses PET as both. The bacteria )] TJ ET BT 61.016 479.093 Td /F4 9.0 Tf [(breaks the PET down to the several components of its monomer units. The group had to do a number of thing identify the )] TJ ET BT 61.016 468.104 Td /F4 9.0 Tf [(enzyme\(s\) concerned and then sequence the protein\(s\) and then determine their 3D structure. An enzyme is a protein )] TJ ET BT 61.016 457.115 Td /F4 9.0 Tf [(\(there are exceptions to this rule\) that speeds up a chemical process but is unchanged by it. Enzymes are highly efficient )] TJ ET BT 61.016 446.126 Td /F4 9.0 Tf [(catalysts. Sequencing the protein is easy but determining its 3D structure is much more difficult. There are 3 ways but the )] TJ ET BT 61.016 435.137 Td /F4 9.0 Tf [(preferred way is to fire x-rays at a protein crystal. X-rays have wavelengths of the order of atomic bonds. They are )] TJ ET BT 61.016 424.148 Td /F4 9.0 Tf [(diffracted by the crystal atoms giving a complex pattern on a detector which must be interpreted by powerful computers. )] TJ ET BT 61.016 413.159 Td /F4 9.0 Tf [(The 3D structure is important because it gives you information on the enzyme family it belongs to in more detail. Also it )] TJ ET BT 61.016 402.170 Td /F4 9.0 Tf [(gives you the mechanism by which it works and may allow modifications and improvements. The group made some )] TJ ET BT 61.016 391.181 Td /F4 9.0 Tf [(modified versions which worked better by mistake! They are now modifying it further to speed up PET breakdown. So far )] TJ ET BT 61.016 380.192 Td /F4 9.0 Tf [(so encouraging. It looks like bacteria are evolving to break down some kinds of plastic. However this does raise some )] TJ ET BT 61.016 369.203 Td /F4 9.0 Tf [(issues. First bacteria will prefer to break down simpler molecules if these are available. If you were to engineer the )] TJ ET BT 61.016 358.214 Td /F4 9.0 Tf [(bacterium so it only could use PET as its carbon source \(the obvious solution\) then it still may revert to suing simpler )] TJ ET BT 61.016 347.225 Td /F4 9.0 Tf [(carbon sources of which there are many in seawater. In addition its illegal to let GM bacteria loose into the environment at )] TJ ET BT 61.016 336.236 Td /F4 9.0 Tf [(present. Another issue is that plastic ties up carbon that would otherwise be released into the atmosphere. The bacterium )] TJ ET BT 61.016 325.247 Td /F4 9.0 Tf [(will produce CO2, water and biomass from the PET. This in one thing in a controlled recycling environment but different if )] TJ ET BT 61.016 314.258 Td /F4 9.0 Tf [(let loose in the sea. Its important that the biomass is maximised and this then falls to the ocean floor where its carbon is )] TJ ET BT 61.016 303.269 Td /F4 9.0 Tf [(tied up for the long term. These dilemmas are the product of our use of plastic. We have some very hard decisions to )] TJ ET BT 61.016 292.280 Td /F4 9.0 Tf [(make fast. But short of going and capturing nano particles of plastic without capturing plankton \(impossible at present\) )] TJ ET BT 61.016 281.291 Td /F4 9.0 Tf [(which would use a lot of energy anyway, this looks like the best solution to dealing with it so far. Neil)] TJ ET 0.400 0.400 0.400 rg BT 61.016 262.802 Td /F2 9.0 Tf [(Posted in:Materials,One Thing We Have Learnt This Week,Plastic Waste,Uncategorized | | With 0 comments)] TJ ET endstream endobj 8 0 obj << /Type /Font /Subtype /Type1 /Name /F1 /BaseFont /Helvetica-Bold /Encoding /WinAnsiEncoding >> endobj 9 0 obj << /Type /Font /Subtype /Type1 /Name /F2 /BaseFont /Helvetica-Oblique /Encoding /WinAnsiEncoding >> endobj 10 0 obj << /Type /Font /Subtype /Type1 /Name /F3 /BaseFont /Helvetica-BoldOblique /Encoding /WinAnsiEncoding >> endobj 11 0 obj << /Type /Font /Subtype /Type1 /Name /F4 /BaseFont /Helvetica /Encoding /WinAnsiEncoding >> endobj 12 0 obj << /Type /Annot /Subtype /Link /A 13 0 R /Border [0 0 0] /H /I /Rect [ 279.6167 627.4441 327.1277 636.6016 ] >> endobj 13 0 obj << /Type /Action /S /URI /URI (https://phys.org/news/2018-04-plastic-eating-enzyme.html) >> endobj 14 0 obj << /Type /Annot /Subtype /Link /A 15 0 R /Border [0 0 0] /H /I /Rect [ 61.0157 520.8508 223.0157 604.1008 ] >> endobj 15 0 obj << /Type /Action /S /URI /URI (http://www.theoillamp.co.uk/wp-content/uploads/2018/04/pet.png) >> endobj 16 0 obj << /Type /XObject /Subtype /Image /Width 216 /Height 111 /Filter /FlateDecode /DecodeParms << /Predictor 15 /Colors 1 /Columns 216 /BitsPerComponent 8>> /ColorSpace /DeviceGray /BitsPerComponent 8 /Length 1781>> stream xDd]Ǐ+Hdd%+Iz%Ikeeddd12VHHV^I$Y#Ydd^YJ2Ƶ{G3l~w̹{繧.NS%Vb?extWic 0a 0a 0a 0a  aݾίAdې}aUۉ{j$/ :]WmmGЎSVNM;9/_o vX& NbƹF[V oƹN*4?*n'ep8'Z7㈻(ras*3öq.@M fobbyjap[}@.CGcjxܢp+qM\V6_˽@ě*~s^zE;>D10rbw GLB|5%SmT-:DwCyMα^Wgj$E6P?=nNI}g(u*JXo,c!1^Ǫ(7VcguMWg5 @O`&_L!G]}uU.!BM y*J]9/8t_?FK(6NKc2Z'pͼ߶T?3d>q>BFdt[N XLx>rTFHz:F:͌R^ܘtt\}uO^1(aӭ 3]ꓔҰxȮ͇ ]!~&ᴙt,9χz]"r[T0&%] ݎ֕6dT؂ R4?w[-,dA닪UN'yM .Y-BEƎMW'$^`f=| :wf`M,JX.vNDjEV gqC ճiա,c r=m`"Xx gx9#0Q wbd532-hk-xGrSXa@BY,*d|XW&шؚLऀψ8¤8Udx'̜#+v8a@BHB pf;WrH !Fd\j<.g} $ZDd!&엝2/t@&z ,h$MWK4_ױ3ym]CrW: aξvLiN߳$}+ է)zoH 'jn pJ!D=0@[An̨1s\+H\T-֤+S V??EtVոv_f*X6SA׶(X%2;I YM΀m?C;Ϋ[D/7͝9JCHgYY–)t͠Yvקg1M- j Ri?kd@ɻ⼑T#U3I?C\_Ʌ=T%SupF9co +=z^h[wyqdbbO9 YyTzׇ|k<ﻷ"0a 0a 0a 0a 0a -q];?`t9e;rʓ 70vHo(aω-*}/{ugZ62,Ӟ? endstream endobj 17 0 obj << /Type /XObject /Subtype /Image /Width 216 /Height 111 /SMask 16 0 R /Filter /FlateDecode /DecodeParms << /Predictor 15 /Colors 3 /Columns 216 /BitsPerComponent 8>> /ColorSpace /DeviceRGB /BitsPerComponent 8 /Length 93>> stream x1 Omov endstream endobj xref 0 18 0000000000 65535 f 0000000008 00000 n 0000000073 00000 n 0000000119 00000 n 0000000343 00000 n 0000000380 00000 n 0000000518 00000 n 0000000607 00000 n 0000006066 00000 n 0000006178 00000 n 0000006293 00000 n 0000006413 00000 n 0000006521 00000 n 0000006649 00000 n 0000006757 00000 n 0000006884 00000 n 0000006998 00000 n 0000009025 00000 n trailer << /Size 18 /Root 1 0 R /Info 5 0 R >> startxref 9375 %%EOF