trunk/proteinstructure/PdbfilePdb.java

package proteinstructure;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.vecmath.Point3d;

public class PdbfilePdb extends Pdb {
        
        private static final String UNKNOWN_STRING ="Unknown";
        private static final String NULL_chainCode = "A";
        
        private String pdbfile;

        /**
         * Constructs Pdb object reading from pdb file given pdb chain code. Model will be DEFAULT_MODEL
         * @param pdbfile
         * @param pdbChainCode
         * @throws FileNotFoundException
         * @throws IOException
         * @throws PdbfileFormatError
         * @throws PdbChainCodeNotFoundError 
         */
        public PdbfilePdb (String pdbfile, String pdbChainCode) throws FileNotFoundException, IOException, PdbfileFormatError, PdbChainCodeNotFoundError {
                this(pdbfile,pdbChainCode,DEFAULT_MODEL);
        }
        
        /**
         * Constructs Pdb object reading from pdb file given pdb chain code and model serial
         * @param pdbfile
         * @param pdbChainCode
         * @param model_serial
         * @throws FileNotFoundException
         * @throws IOException
         * @throws PdbfileFormatError
         * @throws PdbChainCodeNotFoundError 
         */
        public PdbfilePdb (String pdbfile, String pdbChainCode, int model_serial) throws FileNotFoundException, IOException, PdbfileFormatError, PdbChainCodeNotFoundError {
                this.pdbfile = pdbfile;
                this.model=model_serial;
                this.pdbCode=UNKNOWN_STRING; // we initialise to unknown in case we don't find it in pdb file 
                this.pdbChainCode=pdbChainCode.toUpperCase();   // our convention: chain codes are upper case
                // we set chainCode to pdbChainCode except for case NULL where we use "A"
                this.chainCode=pdbChainCode;
                if (pdbChainCode.equals("NULL")) this.chainCode=NULL_chainCode;
                
                this.sequence=""; // we initialise it to empty string, then is set in read_pdb_data_from_file 
                
                // we initialise the secondary structure to empty, if no sec structure info is found then they remain empty
                this.secondaryStructure = new SecondaryStructure();             
                read_pdb_data_from_file();
                if(!secondaryStructure.isEmpty()) {
                        secondaryStructure.setComment("Author");
                }
                
                // when reading from pdb file we have no information of residue numbers or author's (original) pdb residue number, so we fill the mapping with the residue numbers we know
                //TODO eventually we could assign our own internal residue numbers when reading from pdb and thus this map would be used
                this.resser2pdbresser = new HashMap<Integer, String>();
                this.pdbresser2resser = new HashMap<String, Integer>();
                for (int resser:resser2restype.keySet()){
                        resser2pdbresser.put(resser, String.valueOf(resser));
                        pdbresser2resser.put(String.valueOf(resser), resser);
                }
                
                // initialising atomser2atom from resser_atom2atomserial
                atomser2atom = new HashMap<Integer, String>();
                for (String resser_atom:resser_atom2atomserial.keySet()){
                        int atomserial = resser_atom2atomserial.get(resser_atom);
                        String atom = resser_atom.split("_")[1];
                        atomser2atom.put(atomserial,atom);
                }
        }

        
        
        /**
         * To read the pdb data (atom coordinates, residue serials, atom serials) from file.
         * chainCode gets set to same as pdbChainCode, except if input chain code NULL then chainCode will be 'A'
         * pdbCode gets set to the one parsed in HEADER or to 'Unknown' if not found
         * sequence gets set to the sequence read from ATOM lines (i.e. observed residues only)
         * No insertion codes are parsed or taken into account at the moment. Thus files with 
         * insertion codes will be incorrectly read
         * @param pdbfile
         * @throws FileNotFoundException
         * @throws IOException
         * @throws PdbfileFormatError
         * @throws PdbChainCodeNotFoundError  
         */
        private void read_pdb_data_from_file() throws FileNotFoundException, IOException, PdbfileFormatError, PdbChainCodeNotFoundError {
                resser_atom2atomserial = new HashMap<String,Integer>();
                resser2restype = new HashMap<Integer,String>();
                atomser2coord = new HashMap<Integer,Point3d>();
                atomser2resser = new HashMap<Integer,Integer>();
                Pattern p;
                Matcher m;
                boolean empty = true; // controls whether we don't find any atom line for given pdbChainCode and model
                // we set chainCodeStr (for regex) to pdbChainCode except for case NULL where we use " " (NULL is a blank chain code in pdb files)
                String chainCodeStr=pdbChainCode;
                if (pdbChainCode.equals("NULL")) chainCodeStr=" ";
                
                int thismodel=DEFAULT_MODEL; // we initialise to DEFAULT_MODEL, in case file doesn't have MODEL lines 
                BufferedReader fpdb = new BufferedReader(new FileReader(new File(pdbfile)));
                int linecount=0;
                String line;
                // read first line
                if((line = fpdb.readLine()) != null ) {
                        linecount = 1;
                        // HEADER
                        p = Pattern.compile("^HEADER");
                        m = p.matcher(line);
                        if (m.find()){
                                Pattern ph = Pattern.compile("^HEADER.{56}(\\d\\w{3})");
                                Matcher mh = ph.matcher(line);
                                if (mh.find()) {
                                        pdbCode=mh.group(1).toLowerCase();
                                }
                        } else { // header not found
                                // check whether this is a Casp prediction file
                                p = Pattern.compile("^PFRMAT TS");
                                m = p.matcher(line);
                                if(m.find()) {
                                        // ok, it is
                                        pdbCode = "CASP";
                                } else {
                                        // a HEADER is the minimum we ask at the moment for a pdb file to have, if we don't find it in line 1 we throw an exception
                                        throw new PdbfileFormatError("The pdb file "+pdbfile+" doesn't seem to have the right format");
                                }
                        }
                } else {
                        throw new PdbfileFormatError("The file "+pdbfile+" is empty.");
                }
                // read further lines
                while ((line = fpdb.readLine() ) != null ) {
                        linecount++;
                        // SEQRES
                        //SEQRES   1 A  348  VAL ASN ILE LYS THR ASN PRO PHE LYS ALA VAL SER PHE
                        p = Pattern.compile("^SEQRES.{5}"+chainCodeStr);
                        m = p.matcher(line);
                        if (m.find()){
                                for (int i=19;i<=67;i+=4) {
                                        if (!line.substring(i, i+3).equals("   ")) {
                                                if (AA.threeletter2oneletter(line.substring(i, i+3))!=null) { // for non-standard aas
                                                        sequence+= AA.threeletter2oneletter(line.substring(i, i+3));
                                                } else {
                                                        sequence+= NONSTANDARD_AA_LETTER;
                                                }
                                        }
                                }
                        }
                        // SECONDARY STRUCTURE
                        // helix
                        //HELIX    1   1 LYS A   17  LEU A   26  1
                        //                                                      helix ser                               beg res ser                                     end res ser
                        p = Pattern.compile("^HELIX..(...).{9}"+chainCodeStr+".(....).{6}"+chainCodeStr+".(....)");
                        m = p.matcher(line);
                        if (m.find()){
                                int serial = Integer.valueOf(m.group(1).trim());
                                int beg = Integer.valueOf(m.group(2).trim());
                                int end = Integer.valueOf(m.group(3).trim());
                                String ssId = new Character(SecStrucElement.HELIX).toString()+serial;
                                SecStrucElement ssElem = new SecStrucElement(SecStrucElement.HELIX,beg,end,ssId);
                                secondaryStructure.add(ssElem);
                        }
                        // sheet
                        //SHEET    2   A 5 ILE A  96  THR A  99 -1  N  LYS A  98   O  THR A 107
                        //                       strand ser sheet id                     beg res ser                 end res ser
                        p = Pattern.compile("^SHEET..(...).(...).{7}"+chainCodeStr+"(....).{6}"+chainCodeStr+"(....)");
                        m = p.matcher(line);
                        if (m.find()){
                                int strandSerial = Integer.valueOf(m.group(1).trim());
                                String sheetId = m.group(2).trim();
                                int beg = Integer.valueOf(m.group(3).trim());
                                int end = Integer.valueOf(m.group(4).trim());
                                String ssId = new Character(SecStrucElement.STRAND).toString()+sheetId+strandSerial;
                                SecStrucElement ssElem = new SecStrucElement(SecStrucElement.STRAND,beg,end,ssId);
                                secondaryStructure.add(ssElem);
                        }
                        // we've stored the sec structure info in the strands2begEnd and sheets2strands maps.
                        // the assignment to resser2secstruct is done when we reach the ATOM lines, see below
                        // turn
                        //TURN     1 S1A GLY A  16  GLN A  18     SURFACE
                        //                                                      turn ser                                beg res ser                                     end res ser
                        p = Pattern.compile("^TURN...(...).{9}"+chainCodeStr+"(....).{6}"+chainCodeStr+"(....)");
                        m = p.matcher(line);
                        if (m.find()){
                                int serial = Integer.valueOf(m.group(1).trim());
                                int beg = Integer.valueOf(m.group(2).trim());
                                int end = Integer.valueOf(m.group(3).trim());
                                String ssId = new Character(SecStrucElement.TURN).toString()+serial;
                                SecStrucElement ssElem = new SecStrucElement(SecStrucElement.TURN,beg,end,ssId);
                                secondaryStructure.add(ssElem);
                        }                       
                        // MODEL
                        p = Pattern.compile("^MODEL\\s+(\\d+)");
                        m = p.matcher(line);
                        if (m.find()){
                                thismodel=Integer.parseInt(m.group(1));
                        }
                        if (thismodel!=model) continue; // we skip reading of atom lines if we are not in the desired model
                        // ATOM
                        p = Pattern.compile("^ATOM");
                        m = p.matcher(line);
                        if (m.find()){
                                //                                 serial    atom   res_type      chain            res_ser     x     y     z
                                Pattern pl = Pattern.compile("^.{6}(.....).{2}(...).{1}(...).{1}"+chainCodeStr+"(.{4}).{4}(.{8})(.{8})(.{8})",Pattern.CASE_INSENSITIVE);
                                Matcher ml = pl.matcher(line);
                                if (ml.find()) {
                                        empty=false;
                                        int atomserial=Integer.parseInt(ml.group(1).trim());
                                        String atom = ml.group(2).trim();
                                        String res_type = ml.group(3).trim();
                                        int res_serial = Integer.parseInt(ml.group(4).trim());
                                        double x = Double.parseDouble(ml.group(5).trim());
                                        double y = Double.parseDouble(ml.group(6).trim());
                                        double z = Double.parseDouble(ml.group(7).trim());
                                        Point3d coords = new Point3d(x,y,z);
                                        ArrayList<String> aalist=AA.aas();
                                        if (aalist.contains(res_type)) {
                                                atomser2coord.put(atomserial, coords);
                                                atomser2resser.put(atomserial, res_serial);
                                                resser2restype.put(res_serial, res_type);
                                                ArrayList<String> atomlist = aas2atoms.get(res_type);
                                                if (atomlist.contains(atom)){
                                                        resser_atom2atomserial.put(res_serial+"_"+atom, atomserial);
                                                }
                                        }                                       
                                }
                        }
                }
                fpdb.close();
                if (empty) {
                        //System.err.println("Couldn't find any atom line for given pdbChainCode: "+pdbChainCode+", model: "+model);
                        throw new PdbChainCodeNotFoundError("Couldn't find any ATOM line for given pdbChainCode: "+pdbChainCode+", model: "+model);
                }
                if (sequence.equals("")){
                        // if we couldn't read anything from SEQRES then we read it from the resser2restype HashMap
                        // NOTE: we must make sure elsewhere that there are no unobserved residues, we can't check that here!
                        ArrayList<Integer> ressers = new ArrayList<Integer>();
                        for (int resser:resser2restype.keySet()) {
                                ressers.add(resser);
                        }
                        Collections.sort(ressers);
                        for (int resser:ressers){
                                String oneletter = AA.threeletter2oneletter(resser2restype.get(resser));
                                sequence += oneletter;
                        }
                }
        }
        
}
Revision:	274
Committed:	Tue Aug 14 10:26:32 2007 UTC (17 years, 1 month ago) by stehr
File size:	10650 byte(s)
Log Message:	Added new SecondaryStructure object to Pdb and Graph
Line	User	Rev	File contents
1	duarte	207	package proteinstructure;
2
3			import java.io.BufferedReader;
4			import java.io.File;
5			import java.io.FileNotFoundException;
6			import java.io.FileReader;
7			import java.io.IOException;
8			import java.util.ArrayList;
9			import java.util.Collections;
10			import java.util.HashMap;
11			import java.util.regex.Matcher;
12			import java.util.regex.Pattern;
13
14	duarte	226	import javax.vecmath.Point3d;
15
16	duarte	207	public class PdbfilePdb extends Pdb {
17
18	duarte	208	private static final String UNKNOWN_STRING ="Unknown";
19			private static final String NULL_chainCode = "A";
20
21	duarte	207	private String pdbfile;
22
23			/**
24			* Constructs Pdb object reading from pdb file given pdb chain code. Model will be DEFAULT_MODEL
25			* @param pdbfile
26			* @param pdbChainCode
27			* @throws FileNotFoundException
28			* @throws IOException
29	duarte	208	* @throws PdbfileFormatError
30	stehr	215	* @throws PdbChainCodeNotFoundError
31	duarte	207	*/
32	stehr	215	public PdbfilePdb (String pdbfile, String pdbChainCode) throws FileNotFoundException, IOException, PdbfileFormatError, PdbChainCodeNotFoundError {
33	duarte	207	this(pdbfile,pdbChainCode,DEFAULT_MODEL);
34			}
35
36			/**
37			* Constructs Pdb object reading from pdb file given pdb chain code and model serial
38			* @param pdbfile
39			* @param pdbChainCode
40			* @param model_serial
41			* @throws FileNotFoundException
42			* @throws IOException
43	duarte	208	* @throws PdbfileFormatError
44	stehr	215	* @throws PdbChainCodeNotFoundError
45	duarte	207	*/
46	stehr	215	public PdbfilePdb (String pdbfile, String pdbChainCode, int model_serial) throws FileNotFoundException, IOException, PdbfileFormatError, PdbChainCodeNotFoundError {
47	duarte	207	this.pdbfile = pdbfile;
48			this.model=model_serial;
49	duarte	208	this.pdbCode=UNKNOWN_STRING; // we initialise to unknown in case we don't find it in pdb file
50	stehr	217	this.pdbChainCode=pdbChainCode.toUpperCase(); // our convention: chain codes are upper case
51	duarte	208	// we set chainCode to pdbChainCode except for case NULL where we use "A"
52			this.chainCode=pdbChainCode;
53			if (pdbChainCode.equals("NULL")) this.chainCode=NULL_chainCode;
54
55	duarte	258	this.sequence=""; // we initialise it to empty string, then is set in read_pdb_data_from_file
56	duarte	208
57	stehr	274	// we initialise the secondary structure to empty, if no sec structure info is found then they remain empty
58			this.secondaryStructure = new SecondaryStructure();
59	duarte	207	read_pdb_data_from_file();
60	stehr	274	if(!secondaryStructure.isEmpty()) {
61			secondaryStructure.setComment("Author");
62	stehr	259	}
63	duarte	208
64			// when reading from pdb file we have no information of residue numbers or author's (original) pdb residue number, so we fill the mapping with the residue numbers we know
65			//TODO eventually we could assign our own internal residue numbers when reading from pdb and thus this map would be used
66			this.resser2pdbresser = new HashMap<Integer, String>();
67			this.pdbresser2resser = new HashMap<String, Integer>();
68			for (int resser:resser2restype.keySet()){
69			resser2pdbresser.put(resser, String.valueOf(resser));
70			pdbresser2resser.put(String.valueOf(resser), resser);
71			}
72	duarte	219
73	duarte	237	// initialising atomser2atom from resser_atom2atomserial
74			atomser2atom = new HashMap<Integer, String>();
75			for (String resser_atom:resser_atom2atomserial.keySet()){
76			int atomserial = resser_atom2atomserial.get(resser_atom);
77			String atom = resser_atom.split("_")[1];
78			atomser2atom.put(atomserial,atom);
79			}
80	duarte	207	}
81
82
83
84			/**
85	duarte	219	* To read the pdb data (atom coordinates, residue serials, atom serials) from file.
86			* chainCode gets set to same as pdbChainCode, except if input chain code NULL then chainCode will be 'A'
87	duarte	207	* pdbCode gets set to the one parsed in HEADER or to 'Unknown' if not found
88	duarte	258	* sequence gets set to the sequence read from ATOM lines (i.e. observed residues only)
89	duarte	219	* No insertion codes are parsed or taken into account at the moment. Thus files with
90			* insertion codes will be incorrectly read
91	duarte	207	* @param pdbfile
92			* @throws FileNotFoundException
93			* @throws IOException
94	duarte	208	* @throws PdbfileFormatError
95	stehr	215	* @throws PdbChainCodeNotFoundError
96	duarte	207	*/
97	stehr	215	private void read_pdb_data_from_file() throws FileNotFoundException, IOException, PdbfileFormatError, PdbChainCodeNotFoundError {
98	duarte	207	resser_atom2atomserial = new HashMap<String,Integer>();
99			resser2restype = new HashMap<Integer,String>();
100	duarte	226	atomser2coord = new HashMap<Integer,Point3d>();
101	duarte	207	atomser2resser = new HashMap<Integer,Integer>();
102	stehr	255	Pattern p;
103			Matcher m;
104	duarte	207	boolean empty = true; // controls whether we don't find any atom line for given pdbChainCode and model
105	duarte	208	// we set chainCodeStr (for regex) to pdbChainCode except for case NULL where we use " " (NULL is a blank chain code in pdb files)
106			String chainCodeStr=pdbChainCode;
107			if (pdbChainCode.equals("NULL")) chainCodeStr=" ";
108
109	duarte	207	int thismodel=DEFAULT_MODEL; // we initialise to DEFAULT_MODEL, in case file doesn't have MODEL lines
110			BufferedReader fpdb = new BufferedReader(new FileReader(new File(pdbfile)));
111	duarte	208	int linecount=0;
112	duarte	207	String line;
113	stehr	255	// read first line
114			if((line = fpdb.readLine()) != null ) {
115			linecount = 1;
116	duarte	219	// HEADER
117	stehr	255	p = Pattern.compile("^HEADER");
118			m = p.matcher(line);
119	duarte	207	if (m.find()){
120			Pattern ph = Pattern.compile("^HEADER.{56}(\\d\\w{3})");
121			Matcher mh = ph.matcher(line);
122			if (mh.find()) {
123			pdbCode=mh.group(1).toLowerCase();
124			}
125	stehr	255	} else { // header not found
126			// check whether this is a Casp prediction file
127			p = Pattern.compile("^PFRMAT TS");
128			m = p.matcher(line);
129			if(m.find()) {
130			// ok, it is
131			pdbCode = "CASP";
132			} else {
133			// a HEADER is the minimum we ask at the moment for a pdb file to have, if we don't find it in line 1 we throw an exception
134			throw new PdbfileFormatError("The pdb file "+pdbfile+" doesn't seem to have the right format");
135			}
136	duarte	207	}
137	stehr	255	} else {
138			throw new PdbfileFormatError("The file "+pdbfile+" is empty.");
139			}
140			// read further lines
141			while ((line = fpdb.readLine() ) != null ) {
142			linecount++;
143	duarte	258	// SEQRES
144			//SEQRES 1 A 348 VAL ASN ILE LYS THR ASN PRO PHE LYS ALA VAL SER PHE
145			p = Pattern.compile("^SEQRES.{5}"+chainCodeStr);
146			m = p.matcher(line);
147			if (m.find()){
148			for (int i=19;i<=67;i+=4) {
149			if (!line.substring(i, i+3).equals(" ")) {
150	duarte	261	if (AA.threeletter2oneletter(line.substring(i, i+3))!=null) { // for non-standard aas
151			sequence+= AA.threeletter2oneletter(line.substring(i, i+3));
152	duarte	262	} else {
153			sequence+= NONSTANDARD_AA_LETTER;
154	duarte	261	}
155	duarte	258	}
156			}
157			}
158	duarte	219	// SECONDARY STRUCTURE
159			// helix
160			//HELIX 1 1 LYS A 17 LEU A 26 1
161			// helix ser beg res ser end res ser
162			p = Pattern.compile("^HELIX..(...).{9}"+chainCodeStr+".(....).{6}"+chainCodeStr+".(....)");
163			m = p.matcher(line);
164			if (m.find()){
165			int serial = Integer.valueOf(m.group(1).trim());
166			int beg = Integer.valueOf(m.group(2).trim());
167			int end = Integer.valueOf(m.group(3).trim());
168	stehr	274	String ssId = new Character(SecStrucElement.HELIX).toString()+serial;
169			SecStrucElement ssElem = new SecStrucElement(SecStrucElement.HELIX,beg,end,ssId);
170			secondaryStructure.add(ssElem);
171	duarte	219	}
172			// sheet
173			//SHEET 2 A 5 ILE A 96 THR A 99 -1 N LYS A 98 O THR A 107
174			// strand ser sheet id beg res ser end res ser
175			p = Pattern.compile("^SHEET..(...).(...).{7}"+chainCodeStr+"(....).{6}"+chainCodeStr+"(....)");
176			m = p.matcher(line);
177			if (m.find()){
178			int strandSerial = Integer.valueOf(m.group(1).trim());
179			String sheetId = m.group(2).trim();
180			int beg = Integer.valueOf(m.group(3).trim());
181			int end = Integer.valueOf(m.group(4).trim());
182	stehr	274	String ssId = new Character(SecStrucElement.STRAND).toString()+sheetId+strandSerial;
183			SecStrucElement ssElem = new SecStrucElement(SecStrucElement.STRAND,beg,end,ssId);
184			secondaryStructure.add(ssElem);
185	duarte	219	}
186			// we've stored the sec structure info in the strands2begEnd and sheets2strands maps.
187			// the assignment to resser2secstruct is done when we reach the ATOM lines, see below
188			// turn
189			//TURN 1 S1A GLY A 16 GLN A 18 SURFACE
190			// turn ser beg res ser end res ser
191			p = Pattern.compile("^TURN...(...).{9}"+chainCodeStr+"(....).{6}"+chainCodeStr+"(....)");
192			m = p.matcher(line);
193			if (m.find()){
194			int serial = Integer.valueOf(m.group(1).trim());
195			int beg = Integer.valueOf(m.group(2).trim());
196			int end = Integer.valueOf(m.group(3).trim());
197	stehr	274	String ssId = new Character(SecStrucElement.TURN).toString()+serial;
198			SecStrucElement ssElem = new SecStrucElement(SecStrucElement.TURN,beg,end,ssId);
199			secondaryStructure.add(ssElem);
200	duarte	219	}
201			// MODEL
202	duarte	207	p = Pattern.compile("^MODEL\\s+(\\d+)");
203			m = p.matcher(line);
204			if (m.find()){
205			thismodel=Integer.parseInt(m.group(1));
206			}
207			if (thismodel!=model) continue; // we skip reading of atom lines if we are not in the desired model
208	duarte	219	// ATOM
209	duarte	207	p = Pattern.compile("^ATOM");
210			m = p.matcher(line);
211			if (m.find()){
212	duarte	208	// serial atom res_type chain res_ser x y z
213	duarte	263	Pattern pl = Pattern.compile("^.{6}(.....).{2}(...).{1}(...).{1}"+chainCodeStr+"(.{4}).{4}(.{8})(.{8})(.{8})",Pattern.CASE_INSENSITIVE);
214	duarte	207	Matcher ml = pl.matcher(line);
215			if (ml.find()) {
216			empty=false;
217			int atomserial=Integer.parseInt(ml.group(1).trim());
218			String atom = ml.group(2).trim();
219			String res_type = ml.group(3).trim();
220			int res_serial = Integer.parseInt(ml.group(4).trim());
221			double x = Double.parseDouble(ml.group(5).trim());
222			double y = Double.parseDouble(ml.group(6).trim());
223			double z = Double.parseDouble(ml.group(7).trim());
224	duarte	226	Point3d coords = new Point3d(x,y,z);
225	duarte	207	ArrayList<String> aalist=AA.aas();
226			if (aalist.contains(res_type)) {
227			atomser2coord.put(atomserial, coords);
228			atomser2resser.put(atomserial, res_serial);
229			resser2restype.put(res_serial, res_type);
230			ArrayList<String> atomlist = aas2atoms.get(res_type);
231			if (atomlist.contains(atom)){
232			resser_atom2atomserial.put(res_serial+"_"+atom, atomserial);
233			}
234			}
235			}
236			}
237			}
238			fpdb.close();
239	stehr	215	if (empty) {
240			//System.err.println("Couldn't find any atom line for given pdbChainCode: "+pdbChainCode+", model: "+model);
241			throw new PdbChainCodeNotFoundError("Couldn't find any ATOM line for given pdbChainCode: "+pdbChainCode+", model: "+model);
242			}
243	duarte	258	if (sequence.equals("")){
244			// if we couldn't read anything from SEQRES then we read it from the resser2restype HashMap
245			// NOTE: we must make sure elsewhere that there are no unobserved residues, we can't check that here!
246			ArrayList<Integer> ressers = new ArrayList<Integer>();
247			for (int resser:resser2restype.keySet()) {
248			ressers.add(resser);
249			}
250			Collections.sort(ressers);
251			for (int resser:ressers){
252			String oneletter = AA.threeletter2oneletter(resser2restype.get(resser));
253			sequence += oneletter;
254			}
255	duarte	207	}
256			}
257	duarte	219
258	duarte	207	}