The Rest is Silence (30 page)

“I didn't lose you. You killed yourself.”

It's not that simple. I'm not speaking only of my death. I'm speaking of our disconnection from that which nurtures us.

“I didn't say it was simple.”

And you're not living as if it's simple. We all experience heartbreak, betrayals, loss. We tell stories to each other to make sense of that suffering. You believe that you're done with grief. It's not done with you.

He stands there for a long time.

You'll find love, he says, love that matters and feels like home. But only after you've let me go. Let them all go.

I say nothing, and then he's gone.

I start up in bed, gasping for breath in the darkness. I am puffing like a steam engine, disoriented, tangled in the sheet. I had been running the 26.2 miles from Lowell to our house in Newton on the day my father died but my feet were leaden and I couldn't move them. Once I catch my breath, I flop down, facing the wall. Then someone is rubbing my back, soothing me. I lie there, not frightened at all by that hand.

“Dad?” I whisper. There is no answer.

I have the urge to talk to him about things I don't even know how to bring up with the living. So I do, in a whisper, afraid that my voice will break the spell.

“Did it all happen? Remember casting our lines from the canoe in Moosehead Lake, hoping to catch pike? Just the two of us, best friends spending an easy afternoon together. I loved having you to myself, like in the old days when we were driving for days through New England.”

I try to get the words out, but they fill my mouth, leaving little room for breath. I am so tired. I have to know whether he committed suicide. He did drown. But he didn't leave me a note, and the coroner reported that his blood alcohol level indicated he had been drinking heavily. Perhaps he meant to drown and got drunk to give him the courage to do it. Perhaps he slipped and it was a mistake. Either way, his drinking wasn't an accident, and that was what killed him.

The tapping of a woodpecker on the tin roof wakes me. The hand on my back is gone. The smell of cigar smoke is gone. What continues to confound are the skates he left on my bed before he died.

My third drink, the one I poured before falling asleep, sits nearly full on the floor by the chair. I can smell the juniper berries and I remember. I get up, take the glass to the door, open it, and pour the gin and tonic out. It separates into droplets that, by the time they reach the snow below, are no more than a mist.

Christmas morning. I wake from a dream of my death. A blanket is wrapped around my arms and over my head. I am struggling, unable to breathe. I squirm and my wings are free. I shake my tail feathers and leap from the branch. Up, up and circling the treetops, snow glistening on spruce boughs in the bright sun.

One day soon I will take the train to Montreal. Leroy's name was in
The Globe and Mail
this morning. He recently published work on the genetics of colon cancer that should make screening easier. I wrote to his lab at McGill and got a response from him immediately. He wrote about his efforts in the lab and told me that he and Rachel had married before leaving New York. He invited me to visit them — they have a daughter — but I can't face that right now. He said my “escape,” as he called it, worked well. The RCMP had phoned Rachel to say her passport had been found, along with Leroy's sweater, on the rocks by Herring Cove by a woman walking her retriever. He also wrote:

We had no idea why you put $37,000 into Rachel's account. We were sure you were dead, but then you asked Rachel to send you that money to the bank in Toronto and we thought we'd find you. I looked in telephone directories, online. Nothing. You did a good job of erasing yourself.

It's ironic that your work in L's lab forced the development of biodegradable plastics. They're still finding ways to swamp us in the shit. There's a landfill outside the city here that uses microbes like yours, and I read last week that an Australian environmental organization is hoping to collect the plastic in ocean gyres in nets, bring it ashore, and digest it to CO2 and H20. It all seems too little, too late to me, but you never know.

He said that American authorities had been led to Leach when DNA analysis of the bacteria revealed an engineered plasmid with cassettes that could only have come from his lab. Leach was able to convince them that it was Benny, describing me as a rogue element in his lab. That I stole Rachel's passport to get across the border convinced them, and when the FBI went looking for me, the trail ended on the container ship. They had to assume that I drowned off the coast of Nova Scotia.

It is dark in the cabin by five o'clock. Dark and cold. The fire has gone out. I light a candle. I speak with the dead. They haunt me because they
are
me. I climb into the rafters of this tiny cabin and pull down the boxes of letters and photos I have stored. As if happiness can be hoarded for lean nights. The two days I am most concerned with don't exist.

It is time to bury yesterday. Tomorrow will look after itself.

I open the wood stove door and handle each letter. I remember what is in every one. Letters from Katharine. Lay them on top of the cold ashes. A card from my mother when I left home for the first time, to go to summer camp. She was sad and wrote that she'd miss me. The few from my father that I've cherished. More from Lina.

I strike a match and touch it to the pile.

In my hands is the photo of my dad laughing as he holds me over Crystal Lake. I am wearing the blue bathing suit with the frilly skirt that I adored. He looks so happy. I had trusted him to protect me. I throw it into the fire. The flames change the colour of his face and erase his smile.

I close the door when it's all in the fire. Once the fire dies down I take the ashes from the wood stove and put them in a bowl. I unscrew the cap of the gin bottle and smell the juniper. I take a small sip, enough to coat my tongue, and hold it there. I put on my rubber boots and a sweater and go out into the cold. The stars are magnificent. I find the oak Lina and I planted on my birthday. I sprinkle the ashes around its stem, then pour the remaining gin on top of them. This oak has been through a lot. Back in my cabin I blow out the candle and go to bed.

I am through with the past.

I have remembered my shortcomings, and my father's, remembered how I loved him and was loved by him, and in so doing I have attempted to resurrect a time that once was. I have longed to be enveloped in the living I knew in New York, not because it was all that much fun, but because it is my past. And that past is forever linked to the past that came before it, back to a time when I was a kid and life was harmless and I was loved. What I am left with is a visit from the past. And a visit is nothing more than a little death.

Ghosts inhabit this world.

The End

I know that we are going to destroy the world that holds us. We are savages, treating the Earth like a toilet, fouling our own nest. We all seem to agree on that now. Our heads have been in the sand since I was a little girl, when we first realized how good we had it and how we were screwing it all up. We knew what we were wreaking and it scared us, most of all because we couldn't see any way of stopping it. So we stick our heads in the sand. The ostrich does this not to become invisible to its foe; it wants to avoid seeing what's coming for it.

What I created will not stop our destruction of the world. What I am doing here at Forest Garden will not make a difference either, but I have no choice. I acted in New York because I cared, and I have to act now because it matters to me still. The world will continue to change, probably for the worse, but it remains a beautiful place to be. And there is hope, people hold on to hope, even the most pessimistic. Leroy and Rachel see, like the rest of us, where we're headed, yet they chose to have a child. They must believe that we can right our wrongs or why would they have done that?

I look out my window onto a sunny morning. It snowed yesterday and all the night too, and the sunlight on the snow is brighter, but in a different way, than on a summer day. It's hard to be pessimistic on a morning with that sun, the snow still clean, and the birds gliding in the light. Why not love this morning? I stretch. The bay continues to empty and refill twice each day in sync with the moon.

A crow flies overhead. Black, sleek, it reminds me of Lina. It looks down, its beak pointing to the ground. It's the birds that give me heart to continue. Birds keep doing what they do, colourful and tenacious, while the world burns.

I stoke the fire I had left to die out and lie down on my bunk. Leroy's premonition came partly true. We both live in Canada. My skates are hanging from a nail on the wall. “We make things happen by believing they will,” he once said to me. “We dream where we're headed, and one day, as if entering that dream, we arrive there.”

I'm the one in the cabin in the woods, alone on a peaceful sunny morning. I jump from the bunk, lace up my boots, put my coat on, grab the skates from the nail on the wall as well as my shovel, and leave the cabin. I walk deep into the forest beside coyote tracks in the snow along the woods road. The tracks come to a pile of rabbit pellets and a rabbit track crossing it perpendicular to the road. The coyote tracks veer off to follow the trail of the rabbit heading into the woods.

The pond is solid and covered with snow. Its edge is rimmed with spruce laden with snow and with the skeletons of maples, highlighted by the white that rests along their stiff branches. I lace up my skates and begin to shovel the ice clear. It becomes the shape of a rink in a fairy tale, all curves and blips and narrow bottlenecks between trees that lead into open spaces. The shovelling warms me up and I throw my coat on the snowbank I just made. I rest my bare palms on my sweater, feeling the comfort of wool and the solid flesh of my healthy body, and look up at the sky. It is blue as only a sky in January can be blue, outlining the spires of the trees that pierce it. I thank the sky, and the sun that casts shadows of branches on the snow and ice, and the cold air that fills my lungs.

We won't survive. That's no reason to stop trying though, no reason to stop caring. There's nothing else we can do.

I begin to skate, feeling the smooth ice beneath my blades.

Some things won't be lost.

Creation and Characterization of a Polyethylene Terephthalate-Digesting Mutant of
Pseudomonas aeruginosa

Benita R. Mosher, Jonathan Yovkov, Melvin A. Leach*

Department of Microbiology, Cornell University Medical College, New York, New York

Received 6 December ___ /Accepted 12 February ___

Polyethylene terephthalate (PETE), like many petroleum-based polymers, has a half-life of natural degradation exceeding millennia. We report here the creation and selective cultivation of mutant strains of
P. aeruginosa
capable of survival on media containing PETE as the sole source of carbon. These strains apparently cleave PETE in liquid culture, resulting in ethylene glycol as well as other, as yet unknown, short-chain organic compounds. Preliminary analysis of the enzymatic function suggests a novel esterase activity.

Polyethylene terephthalate (PETE) is a condensation polymer resulting from the transesterification of dimethyl terephthalate and ethylene glycol, with methanol as a by-product (Fig. 1). It is one of the most important synthetic polymers and is used in the manufacture of bottles to contain soda and water, food containers, and other liquid containers.

Given its near ubiquity, stability once discarded, and the failure of recycling programs to capture more than 20 per cent of manufactured containers (3), a means of eliminating this waste product from landfills, ditches, and the waterways of the world is essential. There has been a report of a strain of
Pseudomonas
that eats high-density polyethylene (1) but this has not been confirmed.

FIG. 1. Chemical synthesis of polyethylene terephthalate from dimethyl terephthalate and ethylene glycol. The enzymatic breakdown, presumed to be via esterase function in the mutant strains BRM92 and BRM106, releases ethylene glycol and other short-chain compounds yet to be identified.

As part of our ongoing pursuit of sustainable solutions to this problem, we have engineered and/or selected for strains of
P. aeruginosa
(6) and
S. aureus
(2) that are capable of exploiting carbon held within the long-chain polymers that make up various plastics.

We found these strains to be minimally effective in degrading synthetic polymers in liquid culture. Wanting to expand on this work and, hopefully, to discover strains capable of rapidly and efficiently digesting plastics, we used mutagens to create cells with altered properties. These techniques were accompanied by screening and selective pressure to unequivocally identify mutants with the enhanced characteristics.

Through random mutagenesis and selection, we have created a strain of
P. aeruginosa
capable of rapidly degrading PETE in vitro into ethylene glycol and terephthalate.

MATERIALS AND METHODS

Organism
.
Pseudomonas aeruginosa
strain K212 (5) was the wild-type strain used in this study. It was treated with mutagens, followed by selection, resulting in two PETE-digesting strains: BRM92 and BRM106.

Culture conditions
. Single colonies of randomly mutated cells of
P. aeruginosa
K212 were grown in 2X LB medium containing 100 μg/ml carbenicillin and 35 μg/ml tetracycline in 100 ml Erlenmeyer flasks. Cells were spun, washed 3X in distilled water, and resuspended in distilled water containing minimal broth with 100 μg/ml of PETE as the only source of carbon. These liquid cultures were incubated at 300C, observing for cell growth. Cultures not exhibiting any turbidity were discarded after seven days.

Chemicals
. Ethyl methanesulfonate (EMS) was purchased from Blako Chemical Co. (St. Louis, MO). Acridine was purchased from McNeil & Sons Industries (Cleveland, OH). γ-rays were applied using cobalt-60 supplied by Atomic Energy of Canada Ltd. (Chalk River, ON). A circular film of PETE (diameter 65 mm and approximately 750 mg) was obtained from DuPont. Mutagenesis. Liquid cultures of strain K212 were subjected to mutagenesis with each of the agents listed above. They were then grown in minimal broth with PETE. Incubations. 1 ml samples of mutated cells of strain K212 growing in minimal broth with PETE as the sole source of carbon were analyzed using reversed-phaed HPLC. The presence of ethylene glycol was used as a preliminary indication that PETE was being degraded. Those liquid cultures containing significant concentrations of ethylene glycol (>30 mol/L)were subjected to column chromatography.

Detection of PETE-degrading activity using reversed-phase high performance liquid chromatography (HPLC)
. The liquid cultures were analyzed in a Varian ProStar HPLC system. The polar mobile phase used trifluoroacetic acid as an eluent. The eluent had a flow rate of 0.7 ml/min. The column temperature was kept at 32°C.

RESULTS

Random mutagenesis and selection of
P. aeruginosa
K212
. Two cultures of mutagenized K212 grew in minimal liquid media containing PETE as the sole source of carbon. Strain BRM92 resulted from mutagenesis with EMS and strain BRM106 resulted from mutagenesis with gamma rays. Fig. 1 shows the growth profiles of the wild-type and two mutant strains.

FIG. 2. Growth of
P. aeruginosa
strains in minimal liquid medium containing PETE. Strains K212, BRM92, and BRM106 were precultured at 30°C for 2 days in 2X LB medium, triple washed with distilled water, and inoculated into fresh minimal medium with PETE as the sole source of carbon. Cultivation was continued under the same conditions for 80 hours. Cell densities were measured by optical density at 600 nm.

Characterization of strains BRM92 and BRM106
. Lysates of the two mutated strains showed significant degradation products of PETE (Fig. 2). A large peak corresponds to ethylene glycol, one of the expected products of PETE digestion. A smaller significant peak represents terephthalate. There are many other, smaller, peaks representing products that have not yet been analyzed.

FIG. 3. Chromatogram of PETE degradation products. A lysate of strain BM92 was incubated with PETE for 4 hours at 32°C. Peak 1 is ethylene glycol. Peaks 2 is an unknown degradation products to be analyzed. Peak 3 corresponds to terephthalate.

DISCUSSION

In this paper we report the creation of two strains of
P. aeruginosa
capable of growth on medium containing a synthetic compound previously impervious to biological attack. The strains rapidly degrade PETE in vitro into ethylene glycol and terephthalate.

This is a significant find because of the potential to utilize such strains in the degradation of waste products currently disposed of in landfills.

It will be interesting to determine the genetic alteration behind the supposed enzymatic changes that allow these bacterial strains to digest a xenobiotic compound.

ACKNOWLEDGEMENTS

We thank Gabriel Nawthorn and Leroy Timmins for critical reading of the manuscript.

REFERENCES

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   Pseudomonas aeruginosa
   capable of eating vinyl LPs also digests high-density polyethylene. J. Irreprod. Res. 48:38-41.
   
2. Foss, T.L. and M.A. Leach. ____. Selection of strains of
   S. aureus
   for ability to exploit the carbon in polyethylene. J. Biochem. Fund. 27:215-222.
   
3. Burn, S.M. 1991. Social psychology and the stimulation of recycling behaviors: The block leader approach. J. Appl. Soc. Psych. 21:611-629.
   
4. McNeil L., and M. A. Leach. ____. Purification and characterization of an extracellular manganese peroxidase from
   Pseudomonas aeruginosa
   . Microbiol. Symp. 57:62-69.
   
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   P. aeruginosa
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