Spaces:
Sleeping
Sleeping
File size: 35,212 Bytes
ce7bf5b |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 |
# Copyright Generate Biomedicines, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Joint model for protein complexes with applications to unconditional and conditional
protein design in a programmable manner.
"""
import copy
import inspect
from collections import defaultdict, namedtuple
from typing import List, Literal, Optional, Tuple, Union
import torch
import torch.nn as nn
from chroma.constants import AA20_3
from chroma.data.protein import Protein
from chroma.layers.structure.backbone import ProteinBackbone
from chroma.models import graph_backbone, graph_design
class Chroma(nn.Module):
"""Chroma: A generative model for protein design.
Chroma is a generative model for proteins and protein complexes. It combines
a diffusion model for generating protein backbones together with discrete
generative models for sequence and sidechain conformations given structure.
It enables programmatic design of proteins through a conditioning
framework. This class provides an interface to:
* Load model weights
* Sample protein complexes, both unconditionally and conditionally
* Perform sequence design of sampled backbones
Args:
weights_backbone (str, optional): The name of the pre-trained weights
to use for the backbone network.
weights_design (str, optional): The name of the pre-trained weights
to use for the autoregressive design network.
device (Optional[str]): The device on which to load the networks. If
not specified, will automatically use a CUDA device if available,
otherwise CPU.
strict (bool): Whether to strictly enforce that all keys in `weights`
match the keys in the model's state_dict.
verbose (bool, optional): Show outputs from download and loading.
Default False.
GitHub Copilot: 这段注释是对一个名为 "Chroma" 的蛋白质设计生成模型的描述。
Chroma 是一个用于生成蛋白质和蛋白质复合物的模型,它结合了一个用于生成蛋白质骨架的扩散模型,以及一个给定结构的序列和侧链构象的离散生成模型。
它通过一个条件框架实现了蛋白质的程序化设计。这个类提供了以下接口:
* 加载模型权重
* 无条件和有条件地抽样蛋白质复合物
* 对抽样的蛋白质骨架进行序列设计
参数说明:
* weights_backbone (str, 可选): 用于骨架网络的预训练权重的名称。
* weights_design (str, 可选): 用于自回归设计网络的预训练权重的名称。
* device (Optional[str]): 加载网络的设备。如果未指定,将自动使用可用的 CUDA 设备,否则使用 CPU。
* strict (bool): 是否严格要求 `weights` 中的所有键与模型的 state_dict 中的键匹配。
* verbose (bool, 可选): 是否显示下载和加载的输出。默认为 False。
"""
def __init__(
self,
weights_backbone: str = "named:public",
weights_design: str = "named:public",
device: Optional[str] = None,
strict: bool = False,
verbose: bool = False,
) -> None:
super().__init__()
import warnings
warnings.filterwarnings("ignore")
# If no device is explicity specified automatically set device
if device is None:
if torch.cuda.is_available():
device='cuda'
else:
device = "cpu"
print(device)
self.backbone_network = graph_backbone.load_model(
weights_backbone, device=device, strict=strict, verbose=verbose
).eval()
self.design_network = graph_design.load_model(
weights_design,
device=device,
strict=strict,
verbose=False,
).eval()
def sample(
self,
# Backbone Args
samples: int = 1,
steps: int = 500,
chain_lengths: List[int] = [100],
tspan: List[float] = (1.0, 0.001),
protein_init: Protein = None,
conditioner: Optional[nn.Module] = None,
langevin_factor: float = 2,
langevin_isothermal: bool = False,
inverse_temperature: float = 10,
initialize_noise: bool = True,
integrate_func: Literal["euler_maruyama", "heun"] = "euler_maruyama",
sde_func: Literal["langevin", "reverse_sde", "ode"] = "reverse_sde",
trajectory_length: int = 200,
full_output: bool = False,
# Sidechain Args
design_ban_S: Optional[List[str]] = None,
design_method: Literal["potts", "autoregressive"] = "potts",
design_selection: Optional[Union[str, torch.Tensor]] = None,
design_t: Optional[float] = 0.5,
temperature_S: float = 0.01,
temperature_chi: float = 1e-3,
top_p_S: Optional[float] = None,
regularization: Optional[str] = "LCP",
potts_mcmc_depth: int = 500,
potts_proposal: Literal["dlmc", "chromatic"] = "dlmc",
potts_symmetry_order: int = None,
verbose: bool = False,
) -> Union[
Union[Protein, List[Protein]], Tuple[Union[Protein, List[Protein]], dict]
]:
"""
Performs Backbone Sampling and Sequence Design and returns a Protein or list
of Proteins. Optionally this method can return additional arguments to show
details of the sampling procedure.
Args:
Backbone sampling:
samples (int, optional): The number of proteins to sample.
Default is 1.
steps (int, optional): The number of integration steps for the SDE.
Default is 500.
chain_lengths (List[int], optional): The lengths of the protein chains.
Default is [100].
conditioner (Conditioner, optional): The conditioner object that
provides the conditioning information. Default is None.
langevin_isothermal (bool, optional): Whether to use the isothermal
version of the Langevin SDE. Default is False.
integrate_func (str, optional): The name of the integration function to
use. Default is “euler_maruyama”.
sde_func (str, optional): The name of the SDE function to use. Defaults
to “reverse_sde”.
langevin_factor (float, optional): The factor that controls the strength
of the Langevin noise. Default is 2.
inverse_temperature (float, optional): The inverse temperature parameter
for the SDE. Default is 10.
protein_init (Protein, optional): The initial protein state. Defaults
to None.
full_output (bool, optional): Whether to return the full outputs of the
SDE integration, including the protein sample trajectory, the
Xhat trajectory (the trajectory of the preceived denoising target)
and the Xunc trajectory (the trajectory of the unconditional sample
path). Default is False.
initialize_noise (bool, optional): Whether to initialize the noise for
the SDE integration. Default is True.
tspan (List[float], optional): The time span for the SDE integration.
Default is (1.0, 0.001).
trajectory_length (int, optional): The number of sampled steps in the
trajectory output. Maximum is `steps`. Default 200.
**kwargs: Additional keyword arguments for the integration function.
Sequence and sidechain sampling:
design_ban_S (list of str, optional): List of amino acid single-letter
codes to ban, e.g. `["C"]` to ban cysteines.
design_method (str, optional): Specifies which method to use for design.
Can be `potts` and `autoregressive`. Default is `potts`.
design_selection (str, optional): Clamp selection for
conditioning on a subsequence during sequence sampling. Can be
1) a PyMOl-like selection string
(https://pymolwiki.org/index.php/Property_Selectors)
or
2) a binary design mask indicating positions with shape `(num_batch,
num_residues)`. 1. indicating the residue to be designed and
0. indicates the residue will be masked.
e.g.
design_selection = torch.Tensor([[0., 1. ,1., 0., 1. ... ]])
or
3) position-specific valid amino acid choices with shape
`(num_batch, num_residues, num_alphabet)`.
design_t (float or torch.Tensor, optional): Diffusion time for models
trained with diffusion augmentation of input structures. Setting `t=0`
or `t=None` will condition the model to treat the structure as
exact coordinates, while values of `t > 0` will condition
the model to treat structures as though they were drawn from
noise-augmented ensembles with that noise level. For robust design
(default) we recommend `t=0.5`, or for literal design we recommend
`t=0.0`. May be a float or a tensor of shape `(num_batch)`.
temperature_S (float, optional): Temperature for sequence sampling.
Default 0.01.
temperature_chi (float, optional): Temperature for chi angle sampling.
Default 1e-3.
top_p_S (float, optional): Top-p sampling cutoff for autoregressive
sampling.
regularization (str, optional): Complexity regularization for
sampling.
potts_mcmc_depth (int, optional): Depth of sampling (number of steps per
alphabet letter times number of sites) per cycle.
potts_proposal (str): MCMC proposal for Potts sampling. Currently implemented
proposals are `dlmc` (default) for Discrete Langevin Monte Carlo [1] or
`chromatic` for graph-colored block Gibbs sampling.
[1] Sun et al. Discrete Langevin Sampler via Wasserstein Gradient Flow (2023).
potts_symmetry_order (int, optional): Symmetric design.
The first `(num_nodes // symmetry_order)` residues in the protein
system will be variable, and all consecutively tiled sets of residues
will be locked to these during decoding. Internally this is accomplished by
summing the parameters Potts model under a symmetry constraint
into this reduced sized system and then back imputing at the end.
Currently only implemented for Potts models.
Returns:
proteins: Sampled `Protein` object or list of sampled `Protein` objects in
the case of multiple outputs.
full_output_dictionary (dict, optional): Additional outputs if
`full_output=True`.
"""
# Get KWARGS
input_args = locals()
# Dynamically get acceptable kwargs for each method
backbone_keys = set(inspect.signature(self._sample).parameters)
design_keys = set(inspect.signature(self.design).parameters)
# Filter kwargs for each method using dictionary comprehension
backbone_kwargs = {k: input_args[k] for k in input_args if k in backbone_keys}
design_kwargs = {k: input_args[k] for k in input_args if k in design_keys}
# Perform Sampling
sample_output = self._sample(**backbone_kwargs)
if full_output:
protein_sample, output_dictionary = sample_output
else:
protein_sample = sample_output
output_dictionary = None
# Perform Design
if design_method is None:
proteins = protein_sample
else:
if isinstance(protein_sample, list):
proteins = [
self.design(protein, **design_kwargs) for protein in protein_sample
]
else:
proteins = self.design(protein_sample, **design_kwargs)
# Perform conditioner postprocessing
if (conditioner is not None) and hasattr(conditioner, "_postprocessing_"):
proteins, output_dictionary = self._postprocess(
conditioner, proteins, output_dictionary
)
if full_output:
return proteins, output_dictionary
else:
return proteins
def _postprocess(self, conditioner, proteins, output_dictionary):
if output_dictionary is None:
if isinstance(proteins, list):
proteins = [
conditioner._postprocessing_(protein) for protein in proteins
]
else:
proteins = conditioner._postprocessing_(proteins)
else:
if isinstance(proteins, list):
p_dicts = []
proteins = []
for i, protein in enumerate(proteins):
p_dict = {}
for key, value in output_dictionary.items():
p_dict[key] = value[i]
protein, p_dict = conditioner._postprocessing_(protein, p_dict)
p_dicts.append(p_dict)
# Merge Output Dictionaries
output_dictionary = defaultdict(list)
for p_dict in p_dicts:
for k, v in p_dict.items():
output_dictionary[k].append(v)
else:
proteins, output_dictionary = conditioner._postprocessing_(
proteins, output_dictionary
)
return proteins, output_dictionary
def _sample(
self,
samples: int = 1,
steps: int = 500,
chain_lengths: List[int] = [100],
tspan: List[float] = (1.0, 0.001),
protein_init: Protein = None,
conditioner: Optional[nn.Module] = None,
langevin_factor: float = 2,
langevin_isothermal: bool = False,
inverse_temperature: float = 10,
initialize_noise: bool = True,
integrate_func: Literal["euler_maruyama", "heun"] = "euler_maruyama",
sde_func: Literal["langevin", "reverse_sde", "ode"] = "reverse_sde",
trajectory_length: int = 200,
full_output: bool = False,
**kwargs,
) -> Union[
Tuple[List[Protein], List[Protein]],
Tuple[List[Protein], List[Protein], List[Protein], List[Protein]],
]:
"""Samples backbones given chain lengths by integrating SDEs.
其作用是对蛋白质的结构进行采样。该方法通过集成随机微分方程(SDE)来模拟蛋白质的动态行为
Args:
samples (int, optional): The number of proteins to sample. Default is 1.
steps (int, optional): The number of integration steps for the SDE.
Default is 500.
chain_lengths (List[int], optional): The lengths of the protein chains.
Default is [100].
conditioner (Conditioner, optional): The conditioner object that provides
the conditioning information. Default is None.
langevin_isothermal (bool, optional): Whether to use the isothermal version
of the Langevin SDE. Default is False.
integrate_func (str, optional): The name of the integration function to use.
Default is `euler_maruyama`.
sde_func (str, optional): The name of the SDE function to use. Default is
“reverse_sde”.
langevin_factor (float, optional): The factor that controls the strength of
the Langevin noise. Default is 2.
inverse_temperature (float, optional): The inverse temperature parameter
for the SDE. Default is 10.
protein_init (Protein, optional): The initial protein state. Default is
None.
full_output (bool, optional): Whether to return the full outputs of the SDE
integration, including Xhat and Xunc. Default is False.
initialize_noise (bool, optional): Whether to initialize the noise for the
SDE integration. Default is True.
tspan (List[float], optional): The time span for the SDE integration.
Default is (1.0, 0.001).
trajectory_length (int, optional): The number of sampled steps in the
trajectory output. Maximum is `steps`. Default 200.
**kwargs: Additional keyword arguments for the integration function.
Returns:
proteins: Sampled `Protein` object or list of sampled `Protein` objects in
the case of multiple outputs.
full_output_dictionary (dict, optional): Additional outputs if
`full_output=True`.
"""
if protein_init is not None:
X_unc, C_unc, S_unc = protein_init.to_XCS()
else:
X_unc, C_unc, S_unc = self._init_backbones(samples, chain_lengths)
"""
如果提供了初始蛋白质状态,方法将使用它。
否则,它将调用 _init_backbones 方法来初始化蛋白质的背骨。
然后,它将调用 backbone_network.sample_sde 方法来采样SDE。
"""
outs = self.backbone_network.sample_sde(
C_unc,
X_init=X_unc,
conditioner=conditioner,
tspan=tspan,
langevin_isothermal=langevin_isothermal,
integrate_func=integrate_func,
sde_func=sde_func,
langevin_factor=langevin_factor,
inverse_temperature=inverse_temperature,
N=steps,
initialize_noise=initialize_noise,
**kwargs,
)
if S_unc.shape != outs["C"].shape:
S = torch.zeros_like(outs["C"]).long()
else:
S = S_unc
"""
这段代码的目的是确保 `S` 和 `outs["C"]` 的形状相同,这可能是因为在后续的计算中需要它们的形状相同。
如果 `S_unc` 的形状与 `outs["C"]` 不同,那么创建一个新的零张量来代替 `S_unc`。
如果它们的形状不同,`assert` 语句会引发 `AssertionError` 异常。
"""
assert S.shape == outs["C"].shape
proteins = [
Protein.from_XCS(outs_X[None, ...], outs_C[None, ...], outs_S[None, ...])
for outs_X, outs_C, outs_S in zip(outs["X_sample"], outs["C"], S)
]
if samples == 1:
proteins = proteins[0]
if not full_output:
return proteins
else:
outs["S"] = S
trajectories = self._format_trajectory(
outs, "X_trajectory", trajectory_length
)
trajectories_Xhat = self._format_trajectory(
outs, "Xhat_trajectory", trajectory_length
)
# use unconstrained C and S for Xunc_trajectory
outs["S"] = S_unc
outs["C"] = C_unc
trajectories_Xunc = self._format_trajectory(
outs, "Xunc_trajectory", trajectory_length
)
if samples == 1:
full_output_dictionary = {
"trajectory": trajectories[0],
"Xhat_trajectory": trajectories_Xhat[0],
"Xunc_trajectory": trajectories_Xunc[0],
}
else:
full_output_dictionary = {
"trajectory": trajectories,
"Xhat_trajectory": trajectories_Xhat,
"Xunc_trajectory": trajectories_Xunc,
}
return proteins, full_output_dictionary
def _format_trajectory(self, outs, key, trajectory_length):
trajectories = [
Protein.from_XCS_trajectory(
[
outs_X[i][None, ...]
for outs_X in self._resample_trajectory(
trajectory_length, outs[key]
)
],
outs_C[None, ...],
outs_S[None, ...],
)
for i, (outs_C, outs_S) in enumerate(zip(outs["C"], outs["S"]))
]
return trajectories
def _resample_trajectory(self, trajectory_length, trajectory):
if trajectory_length < 0:
raise ValueError(
"The trajectory length must fall on the interval [0, sample_steps]."
)
n = len(trajectory)
trajectory_length = min(n, trajectory_length)
idx = torch.linspace(0, n - 1, trajectory_length).long()
return [trajectory[i] for i in idx]
def design(
self,
protein: Protein,
design_ban_S: Optional[List[str]] = None,
design_method: Literal["potts", "autoregressive"] = "potts",
design_selection: Optional[Union[str, torch.Tensor]] = None,
design_t: Optional[float] = 0.5,
temperature_S: float = 0.01,
temperature_chi: float = 1e-3,
top_p_S: Optional[float] = None,
regularization: Optional[str] = "LCP",
potts_mcmc_depth: int = 500,
potts_proposal: Literal["dlmc", "chromatic"] = "dlmc",
potts_symmetry_order: Optional[int] = None,
verbose: bool = False,
) -> Protein:
"""Performs sequence design and repacking on the specified Protein object
and returns an updated copy.
Args:
protein (Protein): The protein to design.
design_ban_S (list of str, optional): List of amino acid single-letter
codes to ban, e.g. `["C"]` to ban cysteines.
design_method (str, optional): Specifies which method to use for design. valid
methods are potts and autoregressive. Default is potts.
design_selection (str or torch.Tensor, optional): Clamp selection for
conditioning on a subsequence during sequence sampling. Can be
either a selection string or a binary design mask indicating
positions to be sampled with shape `(num_batch, num_residues)` or
position-specific valid amino acid choices with shape
`(num_batch, num_residues, num_alphabet)`.
design_t (float or torch.Tensor, optional): Diffusion time for models
trained with diffusion augmentation of input structures. Setting `t=0`
or `t=None` will condition the model to treat the structure as
exact coordinates, while values of `t > 0` will condition
the model to treat structures as though they were drawn from
noise-augmented ensembles with that noise level. For robust design
(default) we recommend `t=0.5`, or for literal design we recommend
`t=0.0`. May be a float or a tensor of shape `(num_batch)`.
temperature_S (float, optional): Temperature for sequence sampling.
Default 0.01.
temperature_chi (float, optional): Temperature for chi angle sampling.
Default 1e-3.
top_p_S (float, optional): Top-p sampling cutoff for autoregressive
sampling.
regularization (str, optional): Complexity regularization for
sampling.
potts_mcmc_depth (int, optional): Depth of sampling (number of steps per
alphabet letter times number of sites) per cycle.
potts_proposal (str): MCMC proposal for Potts sampling. Currently implemented
proposals are `dlmc` (default) for Discrete Langevin Monte Carlo [1] or
`chromatic` for graph-colored block Gibbs sampling.
[1] Sun et al. Discrete Langevin Sampler via Wasserstein Gradient Flow (2023).
potts_symmetry_order (int, optional): Symmetric design.
The first `(num_nodes // symmetry_order)` residues in the protein
system will be variable, and all consecutively tiled sets of residues
will be locked to these during decoding. Internally this is accomplished by
summing the parameters Potts model under a symmetry constraint
into this reduced sized system and then back imputing at the end.
Currently only implemented for Potts models.
Returns:
A new Protein object with updated sequence and, optionally, side-chains.
"""
protein = copy.deepcopy(protein)
protein.canonicalize()
X, C, S = protein.to_XCS()
if design_method not in set(["potts", "autoregressive"]):
raise NotImplementedError(
"Valid design methods are potts and autoregressive, recieved"
f" {design_method}"
)
# Optional sequence clamping
mask_sample = None
if design_selection is not None:
# 判断design_selection是否为字符串
if isinstance(design_selection, str):
design_selection = protein.get_mask(design_selection)
mask_sample = design_selection
X_sample, S_sample, _ = self.design_network.sample(
X,
C,
S,
t=design_t,
mask_sample=mask_sample,
temperature_S=temperature_S,
temperature_chi=temperature_chi,
ban_S=design_ban_S,
sampling_method=design_method,
regularization=regularization,
potts_sweeps=potts_mcmc_depth,
potts_proposal=potts_proposal,
verbose=verbose,
symmetry_order=potts_symmetry_order,
)
protein.sys.update_with_XCS(X_sample, C=None, S=S_sample)
return protein
def _design_ar(self, protein, alphabet=None, temp_S=0.1, temp_chi=1e-3):
X, C, S = protein.to_XCS()
ban_S = None
if alphabet is not None:
ban_S = set(AA20_3).difference(alphabet)
X_sample, S_sample, _, _ = self.design_network_ar.sample(
X,
C,
S,
temperature_S=temp_S,
temperature_chi=temp_chi,
return_scores=True,
ban_S=ban_S,
)
protein.sys.update_with_XCS(X_sample, C=None, S=S_sample)
return protein
def pack(
self, protein: Protein, temperature_chi: float = 1e-3, clamped: bool = False
) -> Protein:
"""Packs Sidechains of a Protein using the design network
Args:
protein (Protein): The Protein to repack.
temperature_chi (float): Temperature parameter for sampling chi
angles. Even if a high temperature sequence is sampled, this is
recommended to always be low. Default is `1E-3`.
clamped (bool): If `True`, no sampling is done and the likelihood
values will be calculated for the input sequence and structure.
Used for validating the sequential versus parallel decoding
modes. Default is `False`
Returns:
Protein: The Repacked Protein
"""
X, C, S = protein.to_XCS(all_atom=False)
X_repack, _, _ = self.design_network.pack(
X,
C,
S,
temperature_chi=temperature_chi,
clamped=clamped,
return_scores=True,
)
# Convert S_repack to seq
protein.sys.update_with_XCS(X_repack, C=None, S=S)
return protein
def score_backbone(
self,
proteins: Union[List[Protein], Protein],
num_samples: int = 50,
tspan: List[float] = [1e-4, 1.0],
) -> Union[List[dict], dict]:
"""
Score Proteins with the following chroma scores:
elbo:
elbo_X:
rmsd_ratio:
fragment_mse:
neighborhood_mse:
distance_mse:
hb_local:
hb_nonlocal:
Args:
proteins (list of Protein or Protein): The Proteins to be scored.
num_samples (int, optional): The number of time points to calculate the metrics. Default 50.
tspan (list of float, optional): A list of two times [t_initial, t_final] which represent
the range of times to draw samples. Default [1e-4, 1.0].
Returns:
List of dict or dict: A dictionary containing all of the score data.
Scores are returned as named tuples.
"""
# Extract XCS for scoring
device = next(self.parameters()).device
if isinstance(proteins, list):
X, C, S = self._protein_list_to_XCS(proteins, device=device)
else:
X, C, S = proteins.to_XCS(device=device)
# Generate Scores
metrics, metrics_samples = self.backbone_network.estimate_metrics(
X, C, return_samples=True, num_samples=num_samples, tspan=tspan
)
if isinstance(proteins, list):
metric_dictionary = [
self._make_metric_dictionary(metrics, metrics_samples, idx=i)
for i in range(len(proteins))
]
else:
metric_dictionary = self._make_metric_dictionary(metrics, metrics_samples)
return metric_dictionary
def score_sequence(
self,
proteins: Union[List[Protein], Protein],
t: Optional[torch.Tensor] = None,
) -> dict:
"""
Scores designed Proteins with the following Chroma scores:
- -log(p) for sequences and chi angles
- average RMSD and number of clashes per side-chain
For further details on the scores computed, see
chroma.models.graph_design.GraphDesign.loss.
Args:
proteins (list of Protein or Protein): The Proteins to be scored.
t (torch.Tensor, optional): Diffusion timesteps corresponding to
noisy input backbones, of shape `(num_batch)`. Default is no
noise.
Returns:
List of dict or dict: A dictionary containing all of the score data.
Scores are returned as named tuples.
"""
# Extract XCS for scoring
device = next(self.parameters()).device
if isinstance(proteins, list):
X, C, S = self._protein_list_to_XCS(proteins, all_atom=True, device=device)
output_scores = [{} for _ in range(len(proteins))]
else:
X, C, S = proteins.to_XCS(all_atom=True, device=device)
output_scores = {}
losses = self.design_network.loss(X, C, S, t=t, batched=False)
# each value in the losses dictionary contains the results for all proteins
for name, loss_tensor in losses.items():
loss_list = [_t.squeeze() for _t in loss_tensor.split(1)]
if isinstance(proteins, list):
for i, loss in enumerate(loss_list):
output_scores[i][name] = loss
else:
output_scores[name] = loss_list[0]
return output_scores
def _protein_list_to_XCS(self, list_of_proteins, all_atom=False, device=None):
"""Package up proteins with padding"""
# get all the XCS stuff
Xs, Cs, Ss = zip(
*[protein.to_XCS(all_atom=all_atom) for protein in list_of_proteins]
)
# Get Max Dims for Xs, Cs, Ss
Dmax = max([C.shape[1] for C in Cs])
device = Xs[0].device
# Augment each with zeros
with torch.no_grad():
X = torch.cat(
[nn.functional.pad(X, (0, 0, 0, 0, 0, Dmax - X.shape[1])) for X in Xs]
)
C = torch.cat([nn.functional.pad(C, (0, Dmax - C.shape[1])) for C in Cs])
S = torch.cat([nn.functional.pad(S, (0, Dmax - S.shape[1])) for S in Ss])
return X, C, S
def score(
self,
proteins: Union[List[Protein], Protein],
num_samples: int = 50,
tspan: List[float] = [1e-4, 1.0],
) -> Tuple[Union[List[dict], dict], dict]:
backbone_scores = self.score_backbone(proteins, num_samples, tspan)
sequence_scores = self.score_sequence(proteins)
if isinstance(proteins, list):
for ss in sequence_scores:
ss["t_seq"] = ss.pop("t")
return [bs | ss for bs, ss in zip(backbone_scores, sequence_scores)]
else:
sequence_scores["t_seq"] = sequence_scores.pop("t")
return backbone_scores | sequence_scores
def _make_metric_dictionary(self, metrics, metrics_samples, idx=None):
# Process Metrics into a Single Dictionary
metric_dictionary = {}
for k, vs in metrics_samples.items():
if k == "t":
metric_dictionary["t"] = vs
elif k in ["X", "X0_pred"]:
if idx is None:
v = metrics[k]
else:
vs = vs[idx]
v = metrics[k][idx]
score = namedtuple(k, ["value", "samples"])
metric_dictionary[k] = score(value=v, samples=vs)
else:
if idx is None:
v = metrics[k].item()
else:
vs = vs[idx]
v = metrics[k][idx].item()
vs = [i.item() for i in vs]
score = namedtuple(k, ["score", "subcomponents"])
metric_dictionary[k] = score(score=v, subcomponents=vs)
return metric_dictionary
def _init_backbones(self, num_backbones, length_backbones):
# Start with purely alpha backbones
X = ProteinBackbone(
num_batch=num_backbones,
num_residues=sum(length_backbones),
init_state="alpha",
)()
C = torch.cat(
[torch.full([rep], i + 1) for i, rep in enumerate(length_backbones)]
).expand(X.shape[0], -1)
S = torch.zeros_like(C)
return [i.to(next(self.parameters()).device) for i in [X, C, S]]
|