Newer protein-sequencing technologies and a slowdown in demand for its own instrument have prompted Applied Biosystems to shut down its Edman sequencing instrument business.
The company becomes the latest US manufacturer of the technology to leave the market. ABI said it will continue manufacturing the instrument, called Procise until the end of the month and expects to sell the last of them shortly afterward.
For “at least five years” after the shutdown, ABI will continue to provide support to users, including spare parts, technical support, and services, Charles Purtell, senior director and general manager of the consumables business within the proteomics and small-molecule division at ABI, told ProteoMonitor.
The company will continue selling consumables for the platform for an undisclosed “period to come” and has no plans to discontinue that part of the business, he added.
“It’s really just a business decision” to discontinue the Procise line, Purtell said. “It’s a quite a mature market. … It’s a very small business overall for [ABI]. There’s a point at which it no longer makes sense.”
ABI disclosed its decision to close down its Procise business before this week’s announcement of its acquisition by Invitrogen [See related story, this issue]. It is unclear whether the deal will affect ABI’s plans for the instrument or to continue supporting its users.
The Procise comes in two models: the regular Procise, which is directed toward higher-throughput but lower-sensitivity applications, and the Procise capillary cLc system, which is meant for higher-sensitivity applications.
Each system comes in options for one, two, or four channels. Depending on the model, the Procise is priced between $145,000 and $220,000. ABI will continue shipping all six configurations of the platform until existing stocks run out, a spokesman for the company said.
Purtell declined to provide sales figures for the Procise and would not disclose the tool’s installed base, but said sales of it had been sliding recently.
“It’s really just a business decision” to discontinue Procise. “It’s quite a mature market [and is] a very small business overall for [ABI]. There’s a point at which it no longer makes sense.”
“There are plenty of ways to do what people are doing,” he said. “And that’s reflected in sales of the business.” ABI offers no direct substitute technology for the Procise, he added.
Out of Options
Once considered the workhorse instrument for protein chemists, Edman sequencers, which made their original debut about 60 years ago, have been replaced by newer protein sequencing methods, including mass spectrometry-based methods, and the technology is now seen as something of an old-school, niche technology.
Still, supporters swear by it. The Association of Biomolecular Resource Facilities maintains an active research group dedicated to the technology. David Chin, senior scientist in biopharm methods development at drug- and medical technology firm Allergan, now contracts out protein sequencing work, but had been using the ABI Procise for about 20 years.
He acknowledged that for some applications, other newer, more sensitive technologies are better than Edman sequencing, but added that Edman sequencing is an orthogonal technique. “With mass spectrometry, what it gives you is a number, and a lot is based on interpretation of that number,” which increases the chances for human error, Chin said. “There are ambiguous sequences that we don’t know.”
Brian Hampton, program director at the University of Maryland School of Medicine’s Center for Vascular and Inflammatory Diseases, uses the Procise to determine N-terminal sequences primarily to control the quality of recombinant proteins, and to determine sites of biologically relevant proteolysis.
“Unfortunately no other technology or methodology has been adopted into the mainstream that can produce the kind of unequivocal data that can be obtained with an automated Edman sequencer,” he told ProteoMonitor in an e-mail. “For example, there are mass spectrometry-based top-down techniques that can fragment intact proteins and determine a portion of the N- and even C-terminal amino acid sequence, but the amount and quality of such data is variable.
“There are affinity labeling techniques for selecting the N-terminal peptide from a proteolytic digest of a protein that show promise, but mass spectrometry-based techniques will be hampered by their inability to distinguish between isobaric amino acids and that MS/MS data typically do not contain structural information for the entire peptide,” Hampton said.
A recent thread on ABRF’s online discussion group focused on ABI’s decision to shut down the Procise instrument business, and the reaction was one of concern and confusion. One poster suggested ABRF commission a group to communicate user needs and expectations to ABI.
While Purtell said that ABI had begun telling customers of its decision months ago, some of the ABRF posters, while aware of rumors about the imminent shutdown, weren’t certain that the company had made a final decision
“I think people probably anticipated this,” Purtell said. “When you don’t see a lot of new development in an area, people begin to wonder. I think the challenge is always reaching the people who are actually using the instruments.”
For those married to the technology, few alternatives exist. In the US, several players, including Beckman Coulter, Agilent Technologies, and Hewlett Packard, had offered Edman sequencers at one time. In recent years, though, they left the space, and once ABI sells the last of its sequencers, new instruments will not be available in the US.
Shimadzu manufactures the PPSQ Series Protein Sequencer, but sells it only in Japan, although a spokesman for Shimadzu’s US subsidiary told ProteoMonitor by e-mail that there have been discussions with its Japanese parent firm to make the platform available in the US. ABI’s decision does not have a “direct effect” on Shimadzu.
“For us it’s a matter of whether we feel it can be sold and whether we can properly support it,” said Kevin McLaughlin of Shimadzu.
In the meanwhile, some users are concerned that once manufacturing of the Procise ceases, they will be left out in the technological wilderness.
“Since they have said that their level of support may be limited by ‘circumstances beyond our reasonable control ... ’ I have strong doubts that full support for the Procise will continue for five years, and I am very concerned about the potential for drastic increases in the cost of their service and consumables,” Hampton said in his e-mail.
“Applied Biosystems has in recent years significantly increased the cost of certain replacement parts and consumables for the Procise after the discontinuance of a competing instrument from Hewlett Packard,” he added.